update dependencies (#96)

* Bump @actions/core from 1.3.0 to 1.6.0

* Bump @actions/github from 4.0.0 to 5.0.0

* Bump @octokit/rest from 18.5.6 to 18.12.0

* Bump strip-ansi from 6.0.0 to 6.0.1

__tests__/main.test.ts

@@ -135,7 +135,7 @@ describe('run: issue', () => {
     process.env.INPUT_DEDUPE_ISSUES = 'true'
   })
 
-  test('does not call octokit.issues.create if create_issues is set to false', () => {
+  test('does not call octokit.rest.issues.create if create_issues is set to false', () => {
     process.env.INPUT_CREATE_ISSUES = 'false'
 
     mocked(Audit).mockImplementation((): any => {