Add on_executing_* hook to extensions

[jkimbo]

Description

So that it's possible to override the execution phase. Also add docs and examples on how to use it.

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Documentation

Issues Fixed or Closed by This PR

• Fixes Feature Request: 'Rejecting' Requests in Extensions #1397

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[codecov]

Codecov Report

Merging #1400 (aed1c24) into main (6f7b5d2) will increase coverage by 0.01%.
The diff coverage is 100.00%.

❗ Current head aed1c24 differs from pull request most recent head 48e7c7d. Consider uploading reports for the commit 48e7c7d to get more accurate results

@@            Coverage Diff             @@
##             main    #1400      +/-   ##
==========================================
+ Coverage   98.09%   98.10%   +0.01%     
==========================================
  Files         118      118              
  Lines        4039     4063      +24     
  Branches      579      588       +9     
==========================================
+ Hits         3962     3986      +24     
  Misses         41       41              
  Partials       36       36              

[botberry]

Thanks for adding the RELEASE.md file!

Here's a preview of the changelog:

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Add on_executing_* hooks to extensions to allow you to override the execution phase of a GraphQL operation.

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Here's the preview release card for twitter:

Here's the tweet text:

🆕 Release (next) is out! Thanks to Jonathan Kim for the PR 👏

Get it here 👉 https://github.com/strawberry-graphql/strawberry/releases/tag/(next)