Replacing require.nil in cmd/mattermost/commands package (#16964)

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

cmd/mattermost/commands/plugin_test.go

@@ -25,9 +25,9 @@ func TestPlugin(t *testing.T) {
 	th.SetConfig(cfg)
 
 	err := os.MkdirAll("./test-plugins", os.ModePerm)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	err = os.MkdirAll("./test-client-plugins", os.ModePerm)
-	require.Nil(t, err)
+	require.NoError(t, err)
 
 	path, _ := fileutils.FindDir("tests")
 
@@ -37,9 +37,9 @@ func TestPlugin(t *testing.T) {
 	assert.Contains(t, output, "Enabled plugin: testplugin")
 
 	fs, err := config.NewFileStore(th.ConfigPath(), false)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	cfsStore, err := config.NewStoreFromBacking(fs, nil, false)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	require.NotNil(t, cfsStore.Get().PluginSettings.PluginStates["testplugin"])
 	assert.True(t, cfsStore.Get().PluginSettings.PluginStates["testplugin"].Enable)
 	cfsStore.Close()
@@ -47,9 +47,9 @@ func TestPlugin(t *testing.T) {
 	output = th.CheckCommand(t, "plugin", "disable", "testplugin")
 	assert.Contains(t, output, "Disabled plugin: testplugin")
 	fs, err = config.NewFileStore(th.ConfigPath(), false)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	cfsStore, err = config.NewStoreFromBacking(fs, nil, false)
-	require.Nil(t, err)
+	require.NoError(t, err)
 	require.NotNil(t, cfsStore.Get().PluginSettings.PluginStates["testplugin"])
 	assert.False(t, cfsStore.Get().PluginSettings.PluginStates["testplugin"].Enable)
 	cfsStore.Close()
@@ -96,7 +96,7 @@ func TestAddPluginPublicKeys(t *testing.T) {
 	th.SetConfig(cfg)
 
 	err := th.RunCommand(t, "plugin", "keys", "add", "pk1")
-	assert.NotNil(t, err)
+	assert.Error(t, err)
 }
 
 func TestDeletePluginPublicKeys(t *testing.T) {