Fix grammatical typos in documentation

[bontail]

Fix grammatical typos in the documentation (grammar only, no behavior change):

• Doc/library/sys.rst: "are is initialized" → "are initialized"
• Doc/library/ast.rst: "rather then" → "rather than"
• Doc/library/compression.zstd.rst: "it's value" → "its value" (two occurrences)

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #33656665 | 📁 Comparing 93c72bd against main (53916ee)

  🔍 Preview build  

4 files changed

± library/ast.html
± library/compression.zstd.html
± library/sys.html
± whatsnew/changelog.html

[miss-islington-app]

Thanks @bontail for the PR, and @picnixz for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15.
🐍🍒⛏🤖

[bedevere-app]

GH-154190 is a backport of this pull request to the 3.15 branch.

[miss-islington-app]

Sorry, @bontail and @picnixz, I could not cleanly backport this to 3.13 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker 40f7fbf4a53d2f2cb0414a22f891d6e7e288280c 3.13

[bedevere-app]

GH-154191 is a backport of this pull request to the 3.14 branch.

[picnixz]

@bontail Can you take care of the backports for Python 3.13? I suspect that the typos won't be there or are in a separate place. Thanks in advance!

[bedevere-app]

GH-154193 is a backport of this pull request to the 3.13 branch.

[bontail]

@picnixz Done — 3.13 backport is up in GH-154193.

You were right: the compression.zstd.rst typo isn't in 3.13 (the module
was added in 3.14), so only the sys.rst and ast.rst fixes applied there.
That's what tripped up the automated backport. Thanks!

[picnixz]

Please also resign the CLA on the 3.15 and 3.14 backports as explained.