.github/workflows: Add workflow_dispatch event trigger (#214)

Update the go/verify workflows and specify the `workflow_dispatch` event
trigger, so operator-framework members can trigger CI runs of these
workflow definitions without having to open "empty" PRs.

Signed-off-by: timflannagan <[email protected]>

Author: timflannagan

.github/workflows/go.yaml

@@ -6,6 +6,7 @@ on:
   pull_request:
     branches:
       - master
+  workflow_dispatch:
 jobs:
   build:
     name: Build

.github/workflows/verify.yml

@@ -6,6 +6,7 @@ on:
   pull_request:
     paths:
       - '**'
+  workflow_dispatch:
 jobs:
   verify:
     runs-on: ubuntu-latest