fix: Redis 6 on Heroku breaks ActionCable config (#4269)

Heroku made some SSL/TLS changes with Redis 6, which is breaking the ActionCable configuration.
Hence providing an environment variable configuration `REDIS_OPENSSL_VERIFY_MODE` to fix that.

set the value `none` for this environment variable in your Heroku installations where breakage occurs.

fixes: #2420

config/cable.yml

@@ -2,6 +2,8 @@ default: &default
   adapter: redis
   url: <%= ENV.fetch('REDIS_URL', 'redis://127.0.0.1:6379') %>
   password: <%= ENV.fetch('REDIS_PASSWORD', nil).presence %>
+  ssl_params: 
+    verify_mode: <%= Chatwoot.redis_ssl_verify_mode %>
   channel_prefix: <%= "chatwoot_#{Rails.env}_action_cable"  %>
 
 development: