refactor: use explicit mocha imports (#341)

packages/google-cloud-videointelligence/smoke-test/.eslintrc.yml

@@ -1,5 +1,3 @@
 ---
-env:
-  mocha: true
 rules:
   no-undef: off

packages/google-cloud-videointelligence/system-test/.eslintrc.yml

@@ -1,5 +1,3 @@
 ---
-env:
-  mocha: true
 rules:
   no-console: off

packages/google-cloud-videointelligence/system-test/video_intelligence_service_smoke_test.js

@@ -14,6 +14,8 @@
 
 'use strict';
 
+const {describe, it} = require('mocha');
+
 describe('VideoIntelligenceServiceSmokeTest', () => {
   it('successfully makes a call to the service', done => {
     const videoIntelligence = require('../src');

packages/google-cloud-videointelligence/test/gapic-v1.js

@@ -15,6 +15,7 @@
 'use strict';
 
 const assert = require('assert');
+const {describe, it} = require('mocha');
 
 const videoIntelligenceModule = require('../src');
 

packages/google-cloud-videointelligence/test/gapic-v1beta2.js

@@ -15,6 +15,7 @@
 'use strict';
 
 const assert = require('assert');
+const {describe, it} = require('mocha');
 
 const videoIntelligenceModule = require('../src');
 

packages/google-cloud-videointelligence/test/gapic-v1p1beta1.js

@@ -15,6 +15,7 @@
 'use strict';
 
 const assert = require('assert');
+const {describe, it} = require('mocha');
 
 const videoIntelligenceModule = require('../src');
 

packages/google-cloud-videointelligence/test/gapic-v1p2beta1.js

@@ -15,6 +15,7 @@
 'use strict';
 
 const assert = require('assert');
+const {describe, it} = require('mocha');
 
 const videoIntelligenceModule = require('../src');
 

packages/google-cloud-videointelligence/test/gapic-v1p3beta1.js

@@ -15,6 +15,7 @@
 'use strict';
 
 const assert = require('assert');
+const {describe, it} = require('mocha');
 const {PassThrough} = require('stream');
 
 const videoIntelligenceModule = require('../src');