feat: add DEFAULT_MERGE_STYLE to repository.pull-request section for repo init (#19751)

modules/setting/repository.go

@@ -71,6 +71,7 @@ var (
 			WorkInProgressPrefixes                   []string
 			CloseKeywords                            []string
 			ReopenKeywords                           []string
+			DefaultMergeStyle                        string
 			DefaultMergeMessageCommitsLimit          int
 			DefaultMergeMessageSize                  int
 			DefaultMergeMessageAllAuthors            bool
@@ -192,6 +193,7 @@ var (
 			WorkInProgressPrefixes                   []string
 			CloseKeywords                            []string
 			ReopenKeywords                           []string
+			DefaultMergeStyle                        string
 			DefaultMergeMessageCommitsLimit          int
 			DefaultMergeMessageSize                  int
 			DefaultMergeMessageAllAuthors            bool
@@ -205,6 +207,7 @@ var (
 			// https://help.github.com/articles/closing-issues-via-commit-messages
 			CloseKeywords:                            strings.Split("close,closes,closed,fix,fixes,fixed,resolve,resolves,resolved", ","),
 			ReopenKeywords:                           strings.Split("reopen,reopens,reopened", ","),
+			DefaultMergeStyle:                        "merge",
 			DefaultMergeMessageCommitsLimit:          50,
 			DefaultMergeMessageSize:                  5 * 1024,
 			DefaultMergeMessageAllAuthors:            false,