Add headers to fetchAlbum HTTP request

[IvoneDjaja]

Add Accept header and Content-Type header to fix fetchAlbum returning 403 on mobile.

Fix: #13184

PRs or commits this PR depends on (if any):

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[gemini-code-assist]

Code Review

This PR aims to fix an issue by adding headers to an HTTP request in a code example. However, the change is made directly in a markdown file that appears to be generated from a source file, so the change might be lost. I've left a comment pointing to the correct file to modify. I also provided feedback on the headers themselves, suggesting to only include the Accept header for a GET request, as Content-Type is redundant.

[parlough]

/gcbrun

[flutter-website-bot]

Visit the preview URL for this PR (updated for commit 439bab7):

https://flutter-docs-prod--pr13185-patch-1-8ywc23a5.web.app