Add ability for local makefile with personal customizations that wouldnt affect remote repo (#35836)

This would allow developers to keep a local file that'd add personal
makefile targets for niche convenience customization without having to
have the git workspace polluted with uncommitted changes.

---------

Signed-off-by: techknowlogick <techknowlogick@gitea.com>

Author: techknowlogick

.gitattributes

@@ -8,3 +8,4 @@
 /vendor/** -text -eol linguist-vendored
 /web_src/js/vendor/** -text -eol linguist-vendored
 Dockerfile.* linguist-language=Dockerfile
+Makefile.* linguist-language=Makefile

.gitignore

@@ -127,3 +127,6 @@ prime/
 
 # Ignore worktrees when working on multiple branches
 .worktrees/
+
+# A Makefile for custom make targets
+Makefile.local

Makefile

@@ -198,6 +198,10 @@ TEST_MSSQL_DBNAME ?= gitea
 TEST_MSSQL_USERNAME ?= sa
 TEST_MSSQL_PASSWORD ?= MwantsaSecurePassword1
 
+# Include local Makefile
+# Makefile.local is listed in .gitignore
+sinclude Makefile.local
+
 .PHONY: all
 all: build