Shorten test name, correct comment about vtsql credential sequencing

Signed-off-by: notfelineit <notfelineit@gmail.com>

go/vt/vtadmin/vtsql/config.go

@@ -109,7 +109,7 @@ func (c *Config) Parse(args []string) error {
 
 	var username, password string
 
-	// If credentials-path-tmpl is provided, use those credentials instead
+	// First load credentials from credentials-path-tmpl, if provided
 	var tmplStrCreds *grpcclient.StaticAuthClientCreds
 	if *credentialsTmplStr != "" {
 		_creds, path, err := credentials.LoadFromTemplate(*credentialsTmplStr, c)

go/vt/vtadmin/vtsql/config_test.go

@@ -98,7 +98,7 @@ func TestConfigParse(t *testing.T) {
 		assert.Equal(t, expectedCreds, cfg.Credentials)
 	})
 
-	t.Run("it uses vtsql-credentials-password to override file password, if passed", func(t *testing.T) {
+	t.Run("uses vtsql-credentials-password", func(t *testing.T) {
 		t.Parallel()
 
 		f, err := os.CreateTemp("", "vtsql-config-test-testcluster-*") // testcluster is going to appear in the template