internal/ci: improve push_tip_to_trybot defaults

Every parameter to this workflow is itself ultimately a value that can
be derived from the base package parameters. So push the values down.

Whilst we are here, get rid of the separate files for the
push_tip_to_trybot and trybot_dispatch workflows in the github package.
These are one-liners more easily covered in the workflows.cue file.

Also switch to using bashWorkflow in a couple of places instead of
reinventing the wheel.

Signed-off-by: Paul Jolly <paul@myitcv.io>
Change-Id: I0b97fe027452c9b2185858ac2e099fad636dcae8
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/551830
Unity-Result: CUEcueckoo <cueckoo@cuelang.org>
TryBot-Result: CUEcueckoo <cueckoo@cuelang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>

.github/workflows/push_tip_to_trybot.yml

@@ -13,6 +13,7 @@ jobs:
     defaults:
       run:
         shell: bash
+    if: ${{github.repository == 'cue-lang/cue'}}
     steps:
       - name: Write netrc file for cueckoo Gerrithub
         run: |-
@@ -47,4 +48,3 @@ jobs:
           	 echo "Giving up"
           	 exit 1
           fi
-    if: ${{github.repository == 'cue-lang/cue'}}

internal/ci/base/gerrithub.cue

@@ -6,7 +6,7 @@ import (
 	"github.com/SchemaStore/schemastore/src/schemas/json"
 )
 
-trybotDispatchWorkflow: json.#Workflow & {
+trybotDispatchWorkflow: bashWorkflow & {
 	_#branchNameExpression: "\(trybot.key)/${{ github.event.client_payload.payload.changeID }}/${{ github.event.client_payload.payload.commit }}/${{ steps.gerrithub_ref.outputs.gerrithub_ref }}"
 	name:                   "Dispatch \(trybot.key)"
 	on: ["repository_dispatch"]
@@ -50,9 +50,17 @@ trybotDispatchWorkflow: json.#Workflow & {
 	}
 }
 
-pushTipToTrybotWorkflow: json.#Workflow & {
+pushTipToTrybotWorkflow: bashWorkflow & {
 	jobs: [string]: defaults: run: shell: "bash"
 
+	on: {
+		push: branches: protectedBranchPatterns
+	}
+	jobs: push: {
+		"runs-on": linuxMachine
+		if:        "${{github.repository == '\(githubRepositoryPath)'}}"
+	}
+
 	name: "Push tip to \(trybot.key)"
 
 	concurrency: "push_tip_to_trybot"

internal/ci/github/workflows.cue

@@ -40,10 +40,10 @@ import (
 workflows: close({
 	[string]: json.#Workflow
 
-	(_repo.trybot.key):  _
-	trybot_dispatch:    _
+	(_repo.trybot.key): _
+	trybot_dispatch:    _repo.trybotDispatchWorkflow
 	release:            _
 	tip_triggers:       _
-	push_tip_to_trybot: _
+	push_tip_to_trybot: _repo.pushTipToTrybotWorkflow
 	evict_caches:       _
 })