v2.2.1 (#3149)

## Issue Addressed

Addresses sync stalls on v2.2.0 (i.e. https://github.com/sigp/lighthouse/issues/3147).

## Additional Info

I've avoided doing a full `cargo update` because I noticed there's a new patch version of libp2p and thought it could do with some more testing.



Co-authored-by: Paul Hauner <paul@paulhauner.com>

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/v2.2.0-",
+    prefix = "Lighthouse/v2.2.1-",
     fallback = "unknown"
 );