docs: standardize graphql api examples

[melissahenderson]

We'll talk about this before working on it.

Example of what we want will eventually be available at /admin/liquidity/asset-liquidity#deposit-asset-liquidity. #3139 must be completed first.

In general:

• Shorten header to be more direct, don’t include mutation name, don’t include code style
• If any code block is too long, use wrap (```graphql wrap)

Create three tabs.

Operation tab

• Add the mutation to a code block
• Specify graphql as the language

Arguments tab

• Add the JSON request to a code block
• Specify json as the language
• Delete the variable/description table
• Beneath the code block, add For more information about this mutation's input object, see NameOfInputObjectInput. Link the input object to its page in the API docs.

Response tab

• Add the JSON response to a code block
• Specify json as the language