Bump rubocop from 1.27.0 to 1.28.2 (#195)

* Bump rubocop from 1.27.0 to 1.28.2

Bumps [rubocop](https://github.com/rubocop/rubocop) from 1.27.0 to 1.28.2.
- [Release notes](https://github.com/rubocop/rubocop/releases)
- [Changelog](https://github.com/rubocop/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v1.27.0...v1.28.2)

---
updated-dependencies:
- dependency-name: rubocop
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* use ENV.fetch for environment variable accesses

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: david942j <david942j@gmail.com>

Gemfile.lock

@@ -14,11 +14,11 @@ GEM
     elftools (1.1.3)
       bindata (~> 2)
     parallel (1.22.1)
-    parser (3.1.1.0)
+    parser (3.1.2.0)
       ast (~> 2.4.1)
     rainbow (3.1.1)
     rake (13.0.6)
-    regexp_parser (2.3.0)
+    regexp_parser (2.3.1)
     rexml (3.2.5)
     rspec (3.11.0)
       rspec-core (~> 3.11.0)
@@ -33,16 +33,16 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.11.0)
     rspec-support (3.11.0)
-    rubocop (1.27.0)
+    rubocop (1.28.2)
       parallel (~> 1.10)
       parser (>= 3.1.0.0)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.8, < 3.0)
       rexml
-      rubocop-ast (>= 1.16.0, < 2.0)
+      rubocop-ast (>= 1.17.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.16.0)
+    rubocop-ast (1.17.0)
       parser (>= 3.1.1.0)
     ruby-progressbar (1.11.0)
     simplecov (0.21.2)

lib/one_gadget/update.rb

@@ -12,7 +12,7 @@ module Update
     # At least 30 days between check for new version.
     FREQUENCY = 30 * 24 * 60 * 60
     # Path to cache file.
-    CACHE_FILE = File.join(ENV['HOME'], '.cache', 'one_gadget', 'update').freeze
+    CACHE_FILE = File.join(ENV.fetch('HOME', Dir.tmpdir), '.cache', 'one_gadget', 'update').freeze
 
     class << self
       # Check if new releases have been drafted.