fix: ensure empty or devel version valid

As we send the version in our ApiVersionsRequest as the
ClientSoftwareVersion we need to make sure it is considered valid by
Kafka by conforming to their version regex

Author: dnwe

version.go

@@ -15,10 +15,11 @@ func version() string {
 		bi, ok := debug.ReadBuildInfo()
 		if ok {
 			v = bi.Main.Version
-		} else {
+		}
+		if v == "" || v == "(devel)" {
 			// if we can't read a go module version then they're using a git
 			// clone or vendored module so all we can do is report "dev" for
-			// the version
+			// the version to make a valid ApiVersions request
 			v = "dev"
 		}
 	})