PHP: Update note about local development and testing

[stayallive]

DESCRIBE YOUR PR

Clarify the section about local development and testing and point out Spotlight as a option.

Fixes #11337

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Name	Status	Preview	Comments	Updated (UTC)
changelog	❌ Failed (Inspect)			Nov 5, 2024 9:55am
sentry-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Nov 5, 2024 9:55am

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Bundle Report

Changes will increase total bundle size by 459 bytes (0.0%) :arrow_up:. This is within the configured threshold :white_check_mark:

Detailed changes

Bundle name	Size	Change
sentry-docs-server-cjs	7.46MB	6 bytes (-0.0%) :arrow_down:
sentry-docs-edge-server-array-push	257.07kB	3 bytes (-0.0%) :arrow_down:
sentry-docs-client-array-push	6.43MB	468 bytes (0.01%) :arrow_up:

[sfanahata]

@stayallive - I'm doing some cleanup of this repo. Do you still want to move forward with this PR? There are some conflicts as well as some build and deployment failures that are too old for me to check, so if you want to keep this one going, please re-commit your changes and I'll take a look next week.

[stayallive]

We are working some angles, so I'll close this for now and re-submit when needed!