Add admonition about default service port 8080

[cloudflare-workers-and-pages[bot]]

Deploying db2rest-web with    Cloudflare Pages

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[thadguidry]

Hmm, looks like Weird stuff happening with PNG image for D1 Cloudflare docs you wrote and so it's failing build even locally for me. So, Let's first delete the docs/d1 folder and the blogpost #48 (since we don't care about D1 anymore) then we can rerun this PR cloudflare build.

[kdhrubo]

@thadguidry merge conflicts ):

[thadguidry]

@kdhrubo fixed now.