[BUG] Generated Ruby client may contains unexpected interpolation when using enum

Created by: autopp

Bug Report Checklist

Have you provided a full/minimal spec to reproduce the issue?
Have you validated the input using an OpenAPI validator (example)?
What's the version of OpenAPI Generator used?
Have you search for related issues/PRs?
What's the actual output vs expected output?
[Optional] Bounty to sponsor the fix (example)

Description

When using enum, the generated Ruby client code may contain an unexpected interpolation.

openapi-generator version

$ java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar version
4.0.0-SNAPSHOT

$ git log --oneline -n 1
54d9c19c77 (HEAD -> master, origin/master, origin/HEAD) Use https URL to download dependencies (#2248)

OpenAPI declaration file content or url

See: https://gist.github.com/autopp/925901844b9c973fd3c86d06ea95c03a#file-swagger-yml

The point to notice in this example is that #{...} is included in the enum.

Command line used for generation

$ java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate --skip-validate-spec -g ruby -o /tmp/gem -i 'https://gist.githubusercontent.com/autopp/48160b45f1c17c950ba72feb971786c3/raw/974579f49d9a0eebff0455e54efce842eee64c9b/example.yml'

Steps to reproduce

Run the above command to generate client code for Ruby.

lib/openapi_client/api/default_api.rb contains unexpected interpolation

def foo_get_with_http_info(opts = {})
  if @api_client.config.debugging
    @api_client.config.logger.debug 'Calling API: DefaultApi.foo_get ...'
  end
  allowable_values = ["^injected code: #{injected.code}$"]

In this example, injected.code is executed when request to GET /foo (And error may occur).

Related issues/PRs

#2088 (closed)

Suggest a fix

(Same as #2088 (closed)) Curretly, RubyClientCodegen dose not override escapeText. Should not this be overridden to accommodate Ruby's string literal characteristics?