chore: Update codeowners file (#16)

.github/CODEOWNERS

@@ -4,4 +4,22 @@
 # Order is important: the last matching pattern has the highest precedence
 
 # These owners will be the default owners for everything
-* @cloudposse-terraform-components/engineering @cloudposse-terraform-components/admins
+*             @cloudposse-terraform-components/engineering @cloudposse-terraform-components/contributors
+
+# Cloud Posse must review any changes to Makefiles
+**/Makefile   @cloudposse-terraform-components/engineering
+**/Makefile.* @cloudposse-terraform-components/engineering
+
+# Cloud Posse must review any changes to GitHub actions
+.github/*     @cloudposse-terraform-components/engineering
+
+# Cloud Posse must review any changes to standard context definition,
+# but some changes can be rubber-stamped.
+**/*.tf       @cloudposse-terraform-components/engineering @cloudposse-terraform-components/contributors @cloudposse-terraform-components/approvers
+README.yaml   @cloudposse-terraform-components/engineering @cloudposse-terraform-components/contributors @cloudposse-terraform-components/approvers
+README.md     @cloudposse-terraform-components/engineering @cloudposse-terraform-components/contributors @cloudposse-terraform-components/approvers
+docs/*.md     @cloudposse-terraform-components/engineering @cloudposse-terraform-components/contributors @cloudposse-terraform-components/approvers
+
+# Cloud Posse Admins must review all changes to CODEOWNERS or the mergify configuration
+.github/mergify.yml @cloudposse-terraform-components/admins
+.github/CODEOWNERS  @cloudposse-terraform-components/admins