meta: mention nodejs/tsc when changing GH templates

PR-URL: nodejs#49189
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>

.github/CODEOWNERS

@@ -11,6 +11,8 @@
 # tsc
 
 /.github/CODEOWNERS @nodejs/tsc
+/.github/PULL_REQUEST_TEMPLATE.md @nodejs/tsc
+/.github/ISSUE_TEMPLATE/* @nodejs/tsc
 /CODE_OF_CONDUCT.md @nodejs/tsc
 /CONTRIBUTING.md @nodejs/tsc
 /doc/contributing/*.md @nodejs/tsc