gitsync: remove SingleBranch: true

This sets up the remote's tracking in ways that are incompatible with
the wildcard fetching we do later one.

Signed-off-by: Stephan Renatus <stephan.renatus@gmail.com>

Author: srenatus

internal/gitsync/gitsync.go

@@ -189,7 +189,6 @@ func (s *Synchronizer) execute(ctx context.Context) (bool, string, error) {
 			Auth:              authMethod,
 			RecurseSubmodules: git.DefaultSubmoduleRecursionDepth,
 			ReferenceName:     referenceName,
-			SingleBranch:      true,
 			NoCheckout:        true, // We will checkout later
 		})
 		if err != nil {