Remove #process_tag_data indent parameter

As with the previous commits, this indent parameter appears to be a
relic of old usage; the #process_tag_data method has a single caller
that explicitly sets the indent to zero, so the indent parameter and
associated handling can just be removed.

Signed-off-by: Simon Coffey <simon.coffey@futurelearn.com>

lib/git/lib.rb

@@ -261,17 +261,17 @@ def each_cat_file_header(data)
     def tag_data(name)
       sha = sha.to_s
       tdata = command_lines('cat-file', 'tag', name)
-      process_tag_data(tdata, name, 0)
+      process_tag_data(tdata, name)
     end
 
-    def process_tag_data(data, name, indent=4)
+    def process_tag_data(data, name)
       hsh = { 'name' => name }
 
       each_cat_file_header(data) do |key, value|
         hsh[key] = value
       end
 
-      hsh['message'] = data.collect {|line| line[indent..-1]}.join("\n") + "\n"
+      hsh['message'] = data.join("\n") + "\n"
 
       return hsh
     end