integration/phorge: Check for extra (unnecessary) T in URL and strip it

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Proposal

In !145863 (merged) issue tracker support for phorge was added, and I was trying to move from Custom issue tracker to this one.

However, when I just copypasted old value of https://issuetracker.revi.xyz/T:id, it turns out T117 will be rendered as https://issuetracker.revi.xyz/TT117 because phorge's own :id has T already baked in the id format. However the correct value for phorge task number is https://issuetracker.revi.xyz/T117 and browsing TT117 (instead of T117) generates an 404. (Anonymous users will see Log In page because Phorge is thinking you might be lacking proper ACL to see the object, but you see 404 when you are logged in). So, it would be great if it would detect this duplicate when I either "test settings" or "save changes".

Screenshots
num When this config... Shows like this
1 fffce4 c5a9b4
2 d19a80 71341b

In the screenshot, 1 should be prevented or at least should be warned that it is not a valid URL.

For /label I used the labels based on the MR linked above, but if something is incorrect, sorry for that! (And I skipped the Free/Premium/Ultimate because I have no idea which it belongs to.)

Edited by 🤖 GitLab Bot 🤖