add buildah

.github/workflows/build.yaml

@@ -40,7 +40,7 @@ jobs:
 
           # now fix up the images in k/runner.yaml
           sed -i -e "s@image: $DOCKER_REGISTRY/$GITHUB_REPOSITORY:.*@image: $DOCKER_REGISTRY/$GITHUB_REPOSITORY:$STAG@" "k/$DEPLOY_MANIFEST"
-          sed -i -e "s@branch: .*@$KBRANCH@" "k/$FLUX_MANIFEST"
+          sed -i -e "s@branch: .*$@branch: $KBRANCH@" "k/$FLUX_MANIFEST"
 
           git add k
           git commit -m "upgrade runner sts to $STAG"
@@ -49,7 +49,7 @@ jobs:
           # now let's fix the origin branch's flux.yaml if it's needed.
           # this will only happen once so it's not such an awful UX.
           git checkout "$BRANCH"
-          sed -i -e "s@branch: .*@$KBRANCH@" "k/$FLUX_MANIFEST"
+          sed -i -e "s@branch: .*$@branch: $KBRANCH@" "k/$FLUX_MANIFEST"
 
           if git diff | grep -q .;then
             echo fixing branch in flux.yaml of the origin branch

Dockerfile

@@ -6,6 +6,7 @@ RUN apk add \
     nodejs \
     tea \
     curl \
+    buildah \
   --no-cache
 
 USER rootless