Try upload to ghcr.io instead.

Signed-off-by: Nic Cope <nicc@rk0n.org>

Author: negz

.github/workflows/ci.yml

@@ -24,8 +24,10 @@ env:
   XP_VERSION: v1.20.0
 
   # The package to push, without a version tag. The default matches GitHub. For
-  # example xpkg.crossplane.io/crossplane/function-template-go.
-  XPKG: xpkg.crossplane.io/${{ github.repository}}
+  # example xpkg.crossplane.io/crossplane/function-template-go. Note that
+  # xpkg.crossplane.io is just an alias for ghcr.io, so we upload to ghcr.io but
+  # this'll be pulled from xpkg.crossplane.io.
+  XPKG: ghcr.io/${{ github.repository}}
 
   # The package version to push. The default is 0.0.0-gitsha.
   XPKG_VERSION: ${{ inputs.version }}