This commit makes a couple of changes to the `flux-{go,scm}` packages
so that they properly build again:
- The manifests are generated before the compilation of the `flux`
binary.
- The `makedepends` have been updated to require a version of Go
`>=1.16` (which is a requirement for `embed`).
- The `makedepends` have been updated to require a `kustomize` version
`>=3.0` (as we use `transformers`).
Signed-off-by: Hidde Beydals <hello@hidde.co>
