fix: remove whitespace from metadata.yaml (#1442)

this can trip up parsers that read the metadata file.

Co-authored-by: Damiano Donati <[email protected]>

Author: k8s-infra-cherrypick-robot

metadata.yaml

@@ -16,7 +16,7 @@ releaseSeries:
     contract: v1beta1
   - major: 0
     minor: 5
-    contract: v1beta1 
+    contract: v1beta1
   - major: 0
     minor: 6
     contract: v1beta1