Forbid using `strong_memoize_attr` on methods with parameters

What does this MR do and why?

strong_memoize_attr does not support this case yet.

This fixes a problem (#384925 (closed)) with Gitlab::Utils::Override#override run via bin/rake lint:static_verification for the following example:

class A
  include Gitlab::Utils::StrongMemoize

  def do_something
    # ...
  end
  strong_memoize_attr :do_something
end

class EE::A
  extend Gitlab::Utils::Override

  override :do_something
  def do_something
    super
    # ...
  end
end

A.prepend_mod

Note that this fix does not handle method with required parameters such as:

def do_something(required_param)
end

It also side steps a problem where memoized results are wrong due to parameters.

For example:

  # bad
  def expensive_method(limit: 100)
    LoadFromDatabase.with_theta.limit(limit)
  end

  # good
  def expensive_method(limit: 100)
    strong_memoize_with(:expensive_method, limit) do
      LoadFromDatabase.with_theta.limit(limit)
    end
  end

How to set up and validate locally

From #384925 (closed):

1. Apply diff via git apply

diff --git a/lib/gitlab/ci/build/context/build.rb b/lib/gitlab/ci/build/context/build.rb
index a2b330f19b1a..f054c7f7a7e1 100644
--- a/lib/gitlab/ci/build/context/build.rb
+++ b/lib/gitlab/ci/build/context/build.rb
@@ -16,14 +16,13 @@ def initialize(pipeline, attributes = {})
           end
 
           def variables
-            strong_memoize(:variables) do
-              # This is a temporary piece of technical debt to allow us access
-              # to the CI variables to evaluate rules before we persist a Build
-              # with the result. We should refactor away the extra Build.new,
-              # but be able to get CI Variables directly from the Seed::Build.
-              stub_build.scoped_variables
-            end
+            # This is a temporary piece of technical debt to allow us access
+            # to the CI variables to evaluate rules before we persist a Build
+            # with the result. We should refactor away the extra Build.new,
+            # but be able to get CI Variables directly from the Seed::Build.
+            stub_build.scoped_variables
           end
+          strong_memoize_attr :variables
 
           private
 

CTRL+D

2. Run $ bin/rake lint:static_verification
3. See no errors

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.