Release v2.0.0-rc.0 (#2634)

## Proposed Changes

Cut the first release candidate for v2.0.0, in preparation for testing and release this week

## Additional Info

Builds on #2632, which should either be merged first or in the same batch

common/lighthouse_version/src/lib.rs

@@ -16,7 +16,7 @@ pub const VERSION: &str = git_version!(
         // NOTE: using --match instead of --exclude for compatibility with old Git
         "--match=thiswillnevermatchlol"
     ],
-    prefix = "Lighthouse/v1.5.2-",
+    prefix = "Lighthouse/v2.0.0-rc.0-",
     fallback = "unknown"
 );