Add per-hook HTTP method restrictions

test/hooks.json.tmpl

@@ -3,6 +3,7 @@
     "id": "github",
     "execute-command": "{{ .Hookecho }}",
     "command-working-directory": "/",
+    "http-methods": ["POST"],
     "include-command-output-in-response": true,
     "trigger-rule-mismatch-http-response-code": 400,
     "pass-environment-to-command":

test/hooks.yaml.tmpl

@@ -1,4 +1,6 @@
 - id: github
+  http-methods:
+  - POST
   trigger-rule:
     and:
     - match: