Fix URL parsing in gravity.sh - #6689

What does this PR aim to accomplish?

Fix awk command to return the domain even when there is a "@" character in the middle of the URL: "http://domain.com/path@version/file.txt"

The new command first removes the protocol, then removes the "@" character, but only when it appears in the first part, before the domain: "http://username:password@domain.com/file.txt"

The old command removed everything (including the actual domain) before the "@" character, unconditionally.

Fix #6685

How does this PR accomplish the above?

Changing the awk command to use 2 separate gsub calls. One for the protocol and another one to filter credentials. The new command uses a different regex, that removes text only when the "@" character appears before the domain.

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