[CQ] migrate off deprecated URL constructor invocations

[pq]

As of Java 20, URL(uri) is deprecated in favor of URI(uri).toURL().

See: https://bugs.openjdk.org/browse/JDK-8296385?jql=parent%3DJDK-8294241

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[jwren]

LGTM, I tried this change myself, see PR #8319, but I haven't gone back to update the test which my change caused a failure for -- if this passes all the test but all means land it.

[pq]

Ah! I see. Yeah. The ticket is adding handling for IllegalArgumentExceptions.

Thanks!