[rust] Reuse driver mirror URL (when available) to discover Firefox versions (#13941) #8722

Job	Run time
Check	8m 36s
Python	0s
Java	0s
Ruby	0s
.NET	0s
Rust / Build / Build	3m 55s
Rust / Tests (windows) / Tests (windows)	5m 18s
Rust / Tests (ubuntu) / Tests (ubuntu)	5m 9s
Rust / Tests (macos) / Tests (macos)	10m 43s
Rust / Windows Debug	0s
Rust / Linux Stable	0s
Rust / Windows Stable	0s
Rust / Linux Debug	0s
Rust / MacOS Debug	0s
Rust / MacOS Stable	0s
Rust / Release Binaries	0s
	33m 41s

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