test/rubocops: improve test descriptions

[SeekingMeaning]

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While reviewing #10118, I noticed that a lot of context and it descriptions in test/rubocops are somewhat incoherent

For example:

  context "uses_from_macos" do
    it "wrong conditional uses_from_macos order" do

Failures:

  1) RuboCop::Cop::FormulaAudit::DependencyOrder uses_from_macos wrong conditional uses_from_macos order

This PR improves the test descriptions for the following specs:

• test/rubocops/caveats_spec.rb
• test/rubocops/checksum_spec.rb
• test/rubocops/components_redundancy_spec.rb
• test/rubocops/conflicts_spec.rb
• test/rubocops/dependency_order_spec.rb
• test/rubocops/deprecate_disable_spec.rb

Now the previous example looks like this:

  context "when auditing `uses_from_macos`" do
    it "reports an offense if wrong conditional order" do

Failures:

  1) RuboCop::Cop::FormulaAudit::DependencyOrder when auditing `uses_from_macos` reports an offense if wrong conditional order

[BrewTestBot]

Review period will end on 2020-12-25 at 02:16:18 UTC.

[MikeMcQuaid]

Thanks @SeekingMeaning!

[Rylan12]

LGTM. Thanks! A few suggestions

[BrewTestBot]

Review period ended.