chore(ci): split build workflows by fedora version (#525)

force merge since the build can't pass expected checks due to workflow changes

.github/workflows/build-38.yml

@@ -0,0 +1,15 @@
+name: ublue main 38
+on:
+  pull_request:
+  merge_group:
+  schedule:
+    - cron: '15 15 * * *'  # 3pm-ish UTC everyday (timed against official fedora container pushes)
+  workflow_dispatch:
+
+jobs:
+  ublue-38:
+    name: "build ublue-os/*-main:38"
+    uses: ./.github/workflows/reusable-build.yml
+    secrets: inherit
+    with:
+      fedora_version: 38

.github/workflows/build-39.yml

@@ -0,0 +1,15 @@
+name: ublue main 39
+on:
+  pull_request:
+  merge_group:
+  schedule:
+    - cron: '0 15 * * *'  # 3pm-ish UTC everyday (timed against official fedora container pushes)
+  workflow_dispatch:
+
+jobs:
+  ublue-39:
+    name: "build ublue-os/*-main:39"
+    uses: ./.github/workflows/reusable-build.yml
+    secrets: inherit
+    with:
+      fedora_version: 39

.github/workflows/build-40.yml

@@ -0,0 +1,15 @@
+name: ublue main 40
+on:
+  pull_request:
+  merge_group:
+  schedule:
+    - cron: '5 15 * * *'  # 3pm-ish UTC everyday (timed against official fedora container pushes)
+  workflow_dispatch:
+
+jobs:
+  ublue-40:
+    name: "build ublue-os/*-main:40"
+    uses: ./.github/workflows/reusable-build.yml
+    secrets: inherit
+    with:
+      fedora_version: 40