Add build triggers

Include workflows for triggering nightly builds and custom dev builds
from `build-` prefixed branches

.ci/dev-build

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+csource="${BASH_SOURCE[0]}"
+while [ -h "$csource" ] ; do csource="$(readlink "$csource")"; done
+root="$( cd -P "$( dirname "$csource" )/../" && pwd )"
+
+. "${root}/.ci/load-ci.sh"
+
+if [ "${#}" -ne 2 ]; then
+  printf "Usage: %s BRANCH COMMIT_ID\n" "${0}" >&2
+  exit 1
+fi
+
+branch="${1}"
+full_sha="${2}"
+
+if [ -z "${branch}" ]; then
+  failure "Branch variable is unset, required for dev build"
+fi
+if [ -z "${full_sha}" ]; then
+  failure "The full_sha variable is unexpectedly missing, cannot trigger dev build"
+fi
+
+# Trim the reference prefix if needed
+if [[ "${branch}" = *"refs/heads"* ]]; then
+  debug "trimming branch reference value - %s" "${branch}"
+  branch="${branch##*refs/heads/}"
+  debug "trimmed branch value - %s" "${branch}"
+fi
+
+info "Triggering development build %s (%s)" "${tag}" "${full_sha}"
+github_repository_dispatch "vagrant-builders" "build" "commit_id=${full_sha}" "branch=${branch}"

.ci/nightly-build

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+
+csource="${BASH_SOURCE[0]}"
+while [ -h "$csource" ] ; do csource="$(readlink "$csource")"; done
+root="$( cd -P "$( dirname "$csource" )/../" && pwd )"
+
+. "${root}/.ci/load-ci.sh"
+
+if [ "${#}" -ne 1 ]; then
+  printf "Usage: %s COMMIT_ID\n" "${0}" >&2
+  exit 1
+fi
+
+full_sha="${1}"
+
+if [ -z "${full_sha}" ]; then
+  failure "The full_sha variable is unexpectedly missing, cannot trigger nightly build"
+fi
+
+info "Triggering nightly build %s (%s)" "${tag}" "${full_sha}"
+github_repository_dispatch "vagrant-builders" "nightlies" "commit_id=${full_sha}"

.github/workflows/dev-build.yml

@@ -0,0 +1,18 @@
+on:
+  push:
+    branches: 'build-*'
+
+jobs:
+  trigger-build:
+    if: github.repository == 'hashicorp/vagrant'
+    name: Trigger Development Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Code Checkout
+        uses: actions/checkout@v3
+      - name: Trigger Development Build
+        run: ./.ci/dev-build "${BRANCH}" "${COMMIT_ID}"
+        env:
+          HASHIBOT_TOKEN: ${{ secrets.HASHIBOT_TOKEN }}
+          BRANCH: ${{ github.ref_name }}
+          COMMIT_ID: ${{ github.sha }}

.github/workflows/nightlies.yml

@@ -0,0 +1,17 @@
+on:
+  schedule:
+    - cron: 30 22 * * *
+
+jobs:
+  trigger-nightly:
+    if: github.repository == 'hashicorp/vagrant'
+    name: Trigger Nightly Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Code Checkout
+        uses: actions/checkout@v3
+      - name: Trigger Nightly Build
+        run: ./.ci/nightly-build "${COMMIT_ID}"
+        env:
+          HASHIBOT_TOKEN: ${{ secrets.HASHIBOT_TOKEN }}
+          COMMIT_ID: ${{ github.sha }}