ci: migrate centos:8 images to stream

The centos8 builds have been failing today, and it appears to
be because https://www.centos.org/centos-linux-eol/ happened
about 3 years early and the URLs in the image are hard-broken.

https://forums.centos.org/viewtopic.php?f=54&t=78708 has some
info on re-pointing them to a vault subdomain.

The "right" thing to do is to migrate to centos 8 stream, but
I don't see a centos stream docker image from centos.

This commit attempts the manual migration steps to stream.

Let's see how this goes.

.github/workflows/gen_centos8.yml

@@ -20,6 +20,9 @@ jobs:
     runs-on: "ubuntu-latest"
     container: "centos:8"
     steps:
+      - name: "Migrate to CentOS 8 Stream"
+        shell: bash
+        run: "dnf --disablerepo '*' --enablerepo extras swap centos-linux-repos centos-stream-repos && dnf distro-sync"
       - name: "Install config manager"
         shell: bash
         run: "dnf install -y 'dnf-command(config-manager)'"

.github/workflows/gen_centos8_continuous.yml

@@ -22,6 +22,11 @@ jobs:
     runs-on: "ubuntu-latest"
     container: "centos:8"
     steps:
+      - name: "Migrate to CentOS 8 Stream"
+        shell: bash
+        run: |
+          export BUILD_REASON=Schedule
+          dnf --disablerepo '*' --enablerepo extras swap centos-linux-repos centos-stream-repos && dnf distro-sync
       - name: "Install config manager"
         shell: bash
         run: |

.github/workflows/gen_centos8_tag.yml

@@ -10,6 +10,9 @@ jobs:
     runs-on: "ubuntu-latest"
     container: "centos:8"
     steps:
+      - name: "Migrate to CentOS 8 Stream"
+        shell: bash
+        run: "dnf --disablerepo '*' --enablerepo extras swap centos-linux-repos centos-stream-repos && dnf distro-sync"
       - name: "Install config manager"
         shell: bash
         run: "dnf install -y 'dnf-command(config-manager)'"

ci/generate-workflows.py

@@ -529,6 +529,13 @@ cargo build --all --release""",
             ]
 
         if self.container:
+            if self.container == "centos:8":
+                steps += [
+                    RunStep(
+                        "Migrate to CentOS 8 Stream",
+                        "dnf --disablerepo '*' --enablerepo extras swap centos-linux-repos centos-stream-repos && dnf distro-sync"
+                    ),
+                ]
             if ("fedora" in self.container) or ("centos" in self.container):
                 steps += [
                     RunStep(