fix(rtdb): enable support for firebasedatabase.app

[thameezb]

Closes #415

Enables support for Firebase DBs hosted in the EU

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[thameezb]

@googlebot I signed it!

[hiranya911]

Sorry for the delayed response. This somehow fell through the cracks. I just had one suggestion. And please rebase agains the dev branch. We don't directly push to the default branch.

[thameezb]

Rebased onto dev

[hiranya911]

Thanks. LGTM 👍