Use /**/-style comments for MARK annotations

h/t @mokagio in https://github.com/wordpress-mobile/release-toolkit/pull/329\#discussion_r793616509

Author: AliSoftware

lib/fastlane/plugin/wpmreleasetoolkit/helper/ios/ios_l10n_helper.rb

@@ -57,7 +57,7 @@ def self.merge_strings(paths:, output_path: nil)
               duplicates += (string_keys & all_keys_found) # Find duplicates using Array intersection, and add those to duplicates list
               all_keys_found += string_keys
 
-              tmp_file.write("// MARK: - #{File.basename(input_file)}\n\n")
+              tmp_file.write("/* MARK: - #{File.basename(input_file)} */\n\n")
               # Read line-by-line to reduce memory footprint during content copy; Be sure to guess file encoding using the Byte-Order-Mark.
               File.readlines(input_file, mode: 'rb:BOM|UTF-8').each { |line| tmp_file.write(line) }
               tmp_file.write("\n")

spec/test-data/translations/ios_l10n_helper/expected-merged.strings

@@ -1,6 +1,6 @@
 /* Generated File. Do not edit. */
 
-// MARK: - Localizable-utf16.strings
+/* MARK: - Localizable-utf16.strings */
 
 /* Some file header comment here */
 
@@ -14,7 +14,7 @@
    on key 3 */
 "key3" = "string 3";
 
-// MARK: - InfoPlist-utf8.strings
+/* MARK: - InfoPlist-utf8.strings */
 
 "InfoKey1" = "Info String 1";
 "InfoKey2" = "Info String 2️⃣";