RUBY-1092 Update #to_bson methods signatures for bson 4.1 validating_keys arg

Author: estolfo

lib/mongo/dbref.rb

@@ -84,7 +84,7 @@ def initialize(collection, id, database = nil)
     # @return [ String ] The raw BSON.
     #
     # @since 2.1.0
-    def to_bson(buffer = BSON::ByteBuffer.new)
+    def to_bson(buffer = BSON::ByteBuffer.new, validating_keys = nil)
       as_json.to_bson(buffer)
     end
 

lib/mongo/grid/file/chunk.rb

@@ -135,7 +135,7 @@ def initialize(document)
         # @return [ String ] The raw BSON data.
         #
         # @since 2.0.0
-        def to_bson(buffer = BSON::ByteBuffer.new)
+        def to_bson(buffer = BSON::ByteBuffer.new, validating_keys = nil)
           document.to_bson(buffer)
         end
 

lib/mongo/grid/file/info.rb

@@ -198,9 +198,9 @@ def md5
         # @return [ String ] The raw BSON data.
         #
         # @since 2.0.0
-        def to_bson(encoded = ''.force_encoding(BSON::BINARY))
+        def to_bson(buffer = BSON::ByteBuffer.new, validating_keys = nil)
           document[:md5] ||= @client_md5.hexdigest
-          document.to_bson(encoded)
+          document.to_bson(buffer)
         end
 
         # Get the upload date.