Adding support in cache package to check if Artifact Cache service is enabled or not (#1028)

* Added support to check if Artifact cache service is enabled or not.

* enablingForGHES

* added ACTIONS_CACHE_URL in fixtures

* Fix CI

* CI fix

* changed function name

* Function rename

* Updated release

* added test case

* Update RELEASES.md

* Lint errors

* lint

* linting

* lint

* update name to actions service

* Update packages/cache/src/internal/cacheUtils.ts

Co-authored-by: Brian Cristante <33549821+brcrista@users.noreply.github.com>

* review comments

* linting

* linting

* push to start CI

* Update RELEASES.md

* remove extra spaces

* reverting version update

* Revert "reverting version update"

This reverts commit af84eba61e.

* Update RELEASES.md

Co-authored-by: Brian Cristante <33549821+brcrista@users.noreply.github.com>

packages/cache/__tests__/cache.test.ts

@@ -0,0 +1,14 @@
+import * as cache from '../src/cache'
+
+test('isFeatureAvailable returns true if server url is set', () => {
+  try {
+    process.env['ACTIONS_CACHE_URL'] = 'http://cache.com'
+    expect(cache.isFeatureAvailable()).toBe(true)
+  } finally {
+    delete process.env['ACTIONS_CACHE_URL']
+  }
+})
+
+test('isFeatureAvailable returns false if server url is not set', () => {
+  expect(cache.isFeatureAvailable()).toBe(false)
+})