docs: add JitBlox to development resources list

[mdelaat]

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• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
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What is the current behavior?

Issue Number: N/A

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Does this PR introduce a breaking change?

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Other information

[JeanMeche]

Hi,
Angular.io is now in maintenance mode, we're are not updating its content anymore.

Also note that we choose to not port the resource list to the new https://angular.dev doc site.
Thank you for your understanding.