Remove ref pin for standard-rails (#1815)

# What it does

This should allow dependabot to resolve the newer versions of this gem
properly.

Gemfile

@@ -71,7 +71,7 @@ group :development, :test do
   gem "byebug", platforms: [:mri, :mingw, :x64_mingw]
   gem "standard"
   # Temporarily pinning standard-rails until a release after 1.1.0 is cut
-  gem "standard-rails", github: "standardrb/standard-rails", ref: "3570b7ab7c6d6ff36c5f4d26f92044bc47fb62cb"
+  gem "standard-rails"
   gem "factory_bot_rails"
   gem "spy"
   gem "letter_opener"

Gemfile.lock

@@ -1,12 +1,3 @@
-GIT
-  remote: https://github.com/standardrb/standard-rails.git
-  revision: 3570b7ab7c6d6ff36c5f4d26f92044bc47fb62cb
-  ref: 3570b7ab7c6d6ff36c5f4d26f92044bc47fb62cb
-  specs:
-    standard-rails (1.1.0)
-      lint_roller (~> 1.0)
-      rubocop-rails (~> 2.25.0)
-
 GEM
   remote: https://rubygems.org/
   specs:
@@ -177,7 +168,7 @@ GEM
     childprocess (5.0.0)
     chronic (0.10.2)
     concurrent-ruby (1.3.4)
-    connection_pool (2.4.1)
+    connection_pool (2.5.0)
     crass (1.0.6)
     cssbundling-rails (1.4.1)
       railties (>= 6.0.0)
@@ -494,10 +485,10 @@ GEM
     rubocop-performance (1.23.0)
       rubocop (>= 1.48.1, < 2.0)
       rubocop-ast (>= 1.31.1, < 2.0)
-    rubocop-rails (2.25.1)
+    rubocop-rails (2.26.2)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
-      rubocop (>= 1.33.0, < 2.0)
+      rubocop (>= 1.52.0, < 2.0)
       rubocop-ast (>= 1.31.1, < 2.0)
     ruby-progressbar (1.13.0)
     ruby-vips (2.2.2)
@@ -542,6 +533,9 @@ GEM
     standard-performance (1.6.0)
       lint_roller (~> 1.1)
       rubocop-performance (~> 1.23.0)
+    standard-rails (1.2.0)
+      lint_roller (~> 1.0)
+      rubocop-rails (~> 2.26.0)
     statsd-ruby (1.5.0)
     stimulus-rails (1.3.4)
       railties (>= 6.0.0)
@@ -563,7 +557,7 @@ GEM
       nokogiri (>= 1.6, < 2.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    unicode-display_width (3.1.2)
+    unicode-display_width (3.1.3)
       unicode-emoji (~> 4.0, >= 4.0.4)
     unicode-emoji (4.0.4)
     uri (1.0.2)
@@ -643,7 +637,7 @@ DEPENDENCIES
   spy
   square.rb
   standard
-  standard-rails!
+  standard-rails
   stimulus-rails
   store_model
   translation