Workflow manager: only show supported actions

Bug: twpowertools:74
Change-Id: Ia2c407acb302bd477e1e33423570ce095138c396
diff --git a/src/workflows/manager/components/ActionEditor.js b/src/workflows/manager/components/ActionEditor.js
index fbd0bed..971b098 100644
--- a/src/workflows/manager/components/ActionEditor.js
+++ b/src/workflows/manager/components/ActionEditor.js
@@ -92,7 +92,7 @@
           class="select"
           @change=${this._actionCaseChanged}>
         ${map(actionCases, ([actionName, num]) => {
-      if (num == 0) return nothing;
+      if (!kSupportedActions.has(num)) return nothing;
       return html`
           <option value=${num} ?selected=${selectedActionCase == num}>
             ${kActionHeadings[num] ?? actionName}