develop: refactor MySQL Connector/Python dev guide

[wd0517]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-09-04 02:31:47.666168953 +0000 UTC m=+2326272.215184925: ☑️ agreed by Oreoxmt.
• 2023-09-04 03:12:29.69314467 +0000 UTC m=+2328714.242160658: ☑️ agreed by sykp241095.

[Oreoxmt]

/verify

[Oreoxmt]

/approve

[ti-chi-bot]

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #14703.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.2: #14706.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.3: #14707.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #14708.