fix: enable-url-completion input treating the string "false" as true (#307)

* NO-ISSUE Add test

* NO-ISSUE Use core.getBooleanInput() to retrieve boolean input values

* NO-ISSUE npm run build

* NO-ISSUE Delete unused import

__test__/input-helper.unit.test.ts

@@ -0,0 +1,28 @@
+import {getInputs} from '../src/input-helper'
+
+describe('input-helper tests', () => {
+  const ORIGINAL_ENV = process.env
+
+  beforeEach(() => {
+    jest.resetModules()
+    process.env = {...ORIGINAL_ENV}
+  })
+
+  afterAll(() => {
+    process.env = ORIGINAL_ENV
+  })
+
+  test('enableUrlCompletion should be false when "false" is passed', () => {
+    process.env['INPUT_ENABLE-URL-COMPLETION'] = 'false'
+
+    const inputs = getInputs()
+    expect(inputs.enableUrlCompletion).toBe(false)
+  })
+
+  test('enableUrlCompletion should be true when "true" is passed', () => {
+    process.env['INPUT_ENABLE-URL-COMPLETION'] = 'true'
+
+    const inputs = getInputs()
+    expect(inputs.enableUrlCompletion).toBe(true)
+  })
+})