ruby : add encoder begin callback related methods (#3076)

* Lazy run TestBase.whisper

* Fix indentation

* Remove disused GGML_HIP_UMA from Ruby

* Add encoder_begin_callback

* Comment out existing abort mechanism

* Add test for encoder_begin_callback

* Add signatures for encoder_begin_callback related methods

* Update gem date

bindings/ruby/lib/whisper/model/uri.rb

@@ -53,7 +53,7 @@ module Whisper
           http.request request do |response|
             case response
             when Net::HTTPNotModified
-            # noop
+              # noop
             when Net::HTTPOK
               download response
             when Net::HTTPRedirection
@@ -68,7 +68,7 @@ module Whisper
       rescue => err
         if cache_path.exist?
           warn err
-        # Use cache file
+          # Use cache file
         else
           raise
         end