make conda recipe data-loading stricter (#1349)

Contributes to rapidsai/build-planning#72

Proposes using `[]` subsetting instead of `.get()` in templating statements in the conda recipe that read data out of `pyproject.toml`. That'll ensure that we get a big loud build error if changes to `pyproject.toml` remove some sections that the conda recipe expects to exist.

## Notes for Reviewers

### How I tested this

Rendered the recipe.

```shell
git fetch upstream --tags

RAPIDS_DATE_STRING="2408" \
RAPIDS_PACKAGE_VERSION="24.8.0" \
conda render \
  -c conda-forge \
  -c rapidsai-nightly \
  conda/recipes/dask-cuda
```

<details><summary>It looks correct to me (click for details)</summary>

```text
--------------
Hash contents:
--------------
{}
----------
meta.yaml:
----------
package:
  name: dask-cuda
  version: 24.8.0
source:
  path: /Users/jlamb/repos/dask-cuda
build:
  entry_points:
    - dask-cuda-worker = dask_cuda.cli:worker
    - dask-cuda-config = dask_cuda.cli:config
  number: '10'
  script:
    - /Users/jlamb/miniforge3/conda-bld/dask-cuda_1718216576022/_h_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_/bin/python
      -m pip install . -vv
  string: py310_2408_g3a04719_10
requirements:
  host:
    - bzip2 1.0.8 h93a5062_5
    - ca-certificates 2024.6.2 hf0a4a13_0
    - libffi 3.4.2 h3422bc3_5
    - libzlib 1.3.1 hfb2fe0b_1
    - ncurses 6.5 hb89a1cb_0
    - python_abi 3.10 4_cp310
    - tzdata 2024a h0c530f3_0
    - xz 5.2.6 h57fd34a_0
    - yaml 0.2.5 h3422bc3_2
    - libsqlite 3.46.0 hfb93653_0
    - openssl 3.3.1 hfb2fe0b_0
    - readline 8.2 h92ec313_1
    - tk 8.6.13 h5083fa2_1
    - python 3.10.14 h2469fbe_0_cpython
    - attrs 23.2.0 pyh71513ae_0
    - packaging 24.1 pyhd8ed1ab_0
    - pkgutil-resolve-name 1.3.10 pyhd8ed1ab_1
    - pyyaml 6.0.1 py310h2aa6e3c_1
    - rpds-py 0.18.1 py310h947b723_0
    - setuptools 70.0.0 pyhd8ed1ab_0
    - tomlkit 0.12.5 pyha770c72_0
    - wheel 0.43.0 pyhd8ed1ab_1
    - zipp 3.19.2 pyhd8ed1ab_0
    - importlib_resources 6.4.0 pyhd8ed1ab_0
    - pip 24.0 pyhd8ed1ab_0
    - referencing 0.35.1 pyhd8ed1ab_0
    - jsonschema-specifications 2023.12.1 pyhd8ed1ab_0
    - jsonschema 4.22.0 pyhd8ed1ab_0
    - rapids-dependency-file-generator 1.13.11 py_0
    - rapids-build-backend 0.3.1 py_0
  run:
    - pynvml>=11.0.0,<11.5
    - numpy>=1.23,<2.0a0
    - python_abi 3.10.* *_cp310
    - click >=8.1
    - rapids-dask-dependency==24.8.*,>=0.0.0a0
    - numba>=0.57
    - python >=3.10,<3.11.0a0
    - pandas>=1.3
    - zict>=2.0.0
test:
  commands:
    - dask cuda --help
    - dask-cuda-worker --help
    - dask cuda worker --help
    - dask-cuda-config --help
    - dask cuda config --help
  imports:
    - dask_cuda
about:
  dev_url: https://github.com/rapidsai/dask-cuda
  doc_url: https://docs.rapids.ai/api/dask-cuda/stable/
  home: https://github.com/rapidsai/dask-cuda
  license: Apache 2.0
  license_file:
    - ../../../LICENSE
  summary: Utilities for Dask and CUDA interactions
extra:
  copy_test_source_files: true
  final: true
```

</details>

Authors:
  - James Lamb (https://github.com/jameslamb)

Approvers:
  - Bradley Dice (https://github.com/bdice)

URL: #1349

conda/recipes/dask-cuda/meta.yaml

@@ -21,8 +21,8 @@ build:
   script:
     - {{ PYTHON }} -m pip install . -vv
   entry_points:
-    {% for e in data.get("project", {}).get("scripts", {}).items() %}
-    - {{ e|join(" = ") }}
+    {% for entrypoint in data["project"]["scripts"] %}
+    - {{ entrypoint ~ ' = ' ~ data["project"]["scripts"][entrypoint] }}
     {% endfor %}
 
 requirements:
@@ -32,7 +32,7 @@ requirements:
     - rapids-build-backend>=0.3.0,<0.4.0.dev0
   run:
     - python
-    {% for r in data.get("project", {}).get("dependencies", []) %}
+    {% for r in data["project"]["dependencies"] %}
     - {{ r }}
     {% endfor %}
 
@@ -41,18 +41,18 @@ test:
     - dask_cuda
   commands:
     - dask cuda --help
-    {% for e in data.get("project", {}).get("scripts", {}).keys() %}
-    - {{ e }} --help
-    - {{ e|replace("-", " ") }} --help
+    {% for entrypoint in data["project"]["scripts"] %}
+    - {{ entrypoint }} --help
+    - {{ entrypoint|replace("-", " ") }} --help
     {% endfor %}
 
 about:
-  home: {{ data.get("project", {}).get("urls", {}).get("Homepage", "") }}
-  license: {{ data.get("project", {}).get("license", {}).get("text", "") }}
+  home: {{ data["project"]["urls"]["Homepage"] }}
+  license: {{ data["project"]["license"]["text"] }}
   license_file:
-    {% for e in data.get("tool", {}).get("setuptools", {}).get("license-files", []) %}
+    {% for e in data["tool"]["setuptools"]["license-files"] %}
     - ../../../{{ e }}
     {% endfor %}
-  summary: {{ data.get("project", {}).get("description", "") }}
-  dev_url: {{ data.get("project", {}).get("urls", {}).get("Source", "") }}
-  doc_url: {{ data.get("project", {}).get("urls", {}).get("Documentation", "") }}
+  summary: {{ data["project"]["description"] }}
+  dev_url: {{ data["project"]["urls"]["Source"] }}
+  doc_url: {{ data["project"]["urls"]["Documentation"] }}