[#674] Tune git revert command arguments to prevent auto-commit

So that we can use our own commit message when reverting
- add option "--no-commit" to git revert command
- tune git package tests accordingly

src/vcs/git/git_impl.go

@@ -259,7 +259,7 @@ func (g *gitImpl) RevertLocal(path string) error {
 // Current implementation uses a direct call to git
 func (g *gitImpl) RollbackLastCommit() error {
 	report.PostInfo("Reverting changes")
-	return g.traceGit("revert", "--no-gpg-sign", "--no-edit", "HEAD")
+	return g.traceGit("revert", "--no-gpg-sign", "--no-edit", "--no-commit", "HEAD")
 }
 
 // Push runs a git push operation.

src/vcs/git/git_impl_test.go

@@ -474,13 +474,13 @@ func Test_git_revert(t *testing.T) {
 			"git revert command call succeeds",
 			nil,
 			false,
-			[]string{"revert", "--no-gpg-sign", "--no-edit", "HEAD"},
+			[]string{"revert", "--no-gpg-sign", "--no-edit", "--no-commit", "HEAD"},
 		},
 		{
 			"git revert command call fails",
 			errors.New("git revert error"),
 			true,
-			[]string{"revert", "--no-gpg-sign", "--no-edit", "HEAD"},
+			[]string{"revert", "--no-gpg-sign", "--no-edit", "--no-commit", "HEAD"},
 		},
 	}
 	for _, tt := range testFlags {