Bump rubocop-rspec_rails from 2.30.0 to 2.31.0

We're changing the `.rubocop.yml` file because we were getting a
warning:

```
rubocop-rspec_rails extension supports plugin, specify `plugins:
rubocop-rspec_rails` instead of `require: rubocop-rspec_rails` in
.rubocop.yml.  For more information, see
https://docs.rubocop.org/rubocop/plugin_migration_guide.html.
```

Bumps [rubocop-rspec_rails](https://github.com/rubocop/rubocop-rspec_rails) from 2.30.0 to 2.31.0.
- [Release notes](https://github.com/rubocop/rubocop-rspec_rails/releases)
- [Changelog](https://github.com/rubocop/rubocop-rspec_rails/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop/rubocop-rspec_rails/compare/v2.30.0...v2.31.0)

---
updated-dependencies:
- dependency-name: rubocop-rspec_rails
  dependency-version: 2.31.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

.rubocop.yml

@@ -4,7 +4,6 @@ plugins:
   - rubocop-performance
   - rubocop-rails
   - rubocop-rspec
-require:
   - rubocop-rspec_rails
 
 AllCops:

Gemfile

@@ -109,7 +109,7 @@ group :development do
   gem "rubocop-performance", "~> 1.26.1", require: false
   gem "rubocop-rails", "~> 2.33.4", require: false
   gem "rubocop-rspec", "~> 3.7.0", require: false
-  gem "rubocop-rspec_rails", "~> 2.30.0", require: false
+  gem "rubocop-rspec_rails", "~> 2.31.0", require: false
   gem "rvm1-capistrano3", "~> 1.4.0", require: false
   gem "web-console", "~> 4.2.1"
 end

Gemfile.lock

@@ -658,9 +658,10 @@ GEM
     rubocop-rspec (3.7.0)
       lint_roller (~> 1.1)
       rubocop (~> 1.72, >= 1.72.1)
-    rubocop-rspec_rails (2.30.0)
-      rubocop (~> 1.61)
-      rubocop-rspec (~> 3, >= 3.0.1)
+    rubocop-rspec_rails (2.31.0)
+      lint_roller (~> 1.1)
+      rubocop (~> 1.72, >= 1.72.1)
+      rubocop-rspec (~> 3.5)
     ruby-progressbar (1.13.0)
     ruby-rc4 (0.1.5)
     ruby-saml (1.18.1)
@@ -894,7 +895,7 @@ DEPENDENCIES
   rubocop-performance (~> 1.26.1)
   rubocop-rails (~> 2.33.4)
   rubocop-rspec (~> 3.7.0)
-  rubocop-rspec_rails (~> 2.30.0)
+  rubocop-rspec_rails (~> 2.31.0)
   rvm1-capistrano3 (~> 1.4.0)
   sassc-embedded (~> 1.77.5)
   sassc-rails (~> 2.1.2)