chore(repo): use default cache directory (#29390)

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## Current Behavior
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Multiple workspaces using the cache directory is causing mismatches with
the db in the workspace data directory.

## Expected Behavior
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We don't need the separate cache directory so we'll go back to using the
default in the workspace.

## Related Issue(s)
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merged. -->

Fixes #

nx.json

@@ -245,7 +245,6 @@
   "nxCloudId": "62d013ea0852fe0a2df74438",
   "nxCloudUrl": "https://staging.nx.app",
   "parallel": 1,
-  "cacheDirectory": "/tmp/nx-cache",
   "bust": 1,
   "defaultBase": "master"
 }