Remove unnecessary comments

app/models/commit.rb

@@ -25,7 +25,6 @@ class Commit
   DIFF_HARD_LIMIT_FILES = 1000
   DIFF_HARD_LIMIT_LINES = 50000
-  # The SHA can be between 7 and 40 hex characters.
   MIN_SHA_LENGTH = 7
   COMMIT_SHA_PATTERN = /\h{#{MIN_SHA_LENGTH},40}/.freeze
@@ -217,7 +216,6 @@ class Commit
     @raw.respond_to?(method, include_private) || super
   end
-  # Truncate sha to 7 characters
   def short_id
     @raw.short_id(MIN_SHA_LENGTH)
   end

lib/gitlab/diff/diff_refs.rb

@@ -57,8 +57,8 @@ module Gitlab
         length = [sha1.length, sha2.length].min
-        # If either of the shas is below 7 characters in length, we cannot be sure
-        # if they actually refer to the same commit because of hash collision.
+        # If either of the shas is below the minimum length, we cannot be sure
+        # that they actually refer to the same commit because of hash collision.
         return false if length < Commit::MIN_SHA_LENGTH
         sha1[0, length] == sha2[0, length]