Raising error if arguments are provided to version and install commands

[prometherion]

Aims to conform to the same behavior with other commands: install and version ones are not expecting to receive arguments, so raising the error errorWantedNoArgs.
In addition, provided some little test coverage and added the required flags for the install command since --git-email was missing but marked as mandatory.

Pretty sure the change is breaking for users using the installation method via the CLI instead of the Helm Chart: they could have automation scripts that are pushing arguments and these could break.

Closes #2808

[2opremio]

Thanks a lot!

[2opremio]

Ah, crap, I should had waited for CI. I would have sworn to have seen a green tick.

[prometherion]

Nevermind, JFI sharing my test suite result:

ok      github.com/fluxcd/flux/cmd/fluxctl      0.274s
?       github.com/fluxcd/flux/cmd/fluxd        [no test files]
?       github.com/fluxcd/flux/integrations/apis/flux.weave.works       [no test files]
ok      github.com/fluxcd/flux/integrations/apis/flux.weave.works/v1beta1       0.011s
?       github.com/fluxcd/flux/integrations/apis/helm.integrations.flux.weave.works     [no test files]
ok      github.com/fluxcd/flux/integrations/apis/helm.integrations.flux.weave.works/v1alpha2    0.023s
?       github.com/fluxcd/flux/integrations/client/clientset/versioned  [no test files]
?       github.com/fluxcd/flux/integrations/client/clientset/versioned/fake     [no test files]
?       github.com/fluxcd/flux/integrations/client/clientset/versioned/scheme   [no test files]
?       github.com/fluxcd/flux/integrations/client/clientset/versioned/typed/flux.weave.works/v1beta1   [no test files]
?       github.com/fluxcd/flux/integrations/client/clientset/versioned/typed/flux.weave.works/v1beta1/fake      [no test files]
?       github.com/fluxcd/flux/integrations/client/clientset/versioned/typed/helm.integrations.flux.weave.works/v1alpha2        [no test files]
?       github.com/fluxcd/flux/integrations/client/clientset/versioned/typed/helm.integrations.flux.weave.works/v1alpha2/fake   [no test files]
?       github.com/fluxcd/flux/integrations/client/informers/externalversions   [no test files]
?       github.com/fluxcd/flux/integrations/client/informers/externalversions/flux.weave.works  [no test files]
?       github.com/fluxcd/flux/integrations/client/informers/externalversions/flux.weave.works/v1beta1  [no test files]
?       github.com/fluxcd/flux/integrations/client/informers/externalversions/helm.integrations.flux.weave.works        [no test files]
?       github.com/fluxcd/flux/integrations/client/informers/externalversions/helm.integrations.flux.weave.works/v1alpha2       [no test files]
?       github.com/fluxcd/flux/integrations/client/informers/externalversions/internalinterfaces        [no test files]
?       github.com/fluxcd/flux/integrations/client/listers/flux.weave.works/v1beta1     [no test files]
?       github.com/fluxcd/flux/integrations/client/listers/helm.integrations.flux.weave.works/v1alpha2  [no test files]
?       github.com/fluxcd/flux/internal/cmd/changelog   [no test files]
?       github.com/fluxcd/flux/pkg/api  [no test files]
?       github.com/fluxcd/flux/pkg/api/v10      [no test files]
?       github.com/fluxcd/flux/pkg/api/v11      [no test files]
ok      github.com/fluxcd/flux/pkg/api/v6       0.040s
ok      github.com/fluxcd/flux/pkg/api/v9       0.015s
?       github.com/fluxcd/flux/pkg/checkpoint   [no test files]
?       github.com/fluxcd/flux/pkg/cluster      [no test files]
ok      github.com/fluxcd/flux/pkg/cluster/kubernetes   33.059s
ok      github.com/fluxcd/flux/pkg/cluster/kubernetes/resource  0.417s
ok      github.com/fluxcd/flux/pkg/cluster/kubernetes/testfiles 0.018s
?       github.com/fluxcd/flux/pkg/cluster/mock [no test files]
ok      github.com/fluxcd/flux/pkg/daemon       73.451s
ok      github.com/fluxcd/flux/pkg/errors       0.038s
ok      github.com/fluxcd/flux/pkg/event        0.018s
ok      github.com/fluxcd/flux/pkg/git  1.148s
ok      github.com/fluxcd/flux/pkg/git/gittest  2.389s
?       github.com/fluxcd/flux/pkg/gpg  [no test files]
?       github.com/fluxcd/flux/pkg/gpg/gpgtest  [no test files]
?       github.com/fluxcd/flux/pkg/guid [no test files]
ok      github.com/fluxcd/flux/pkg/http 0.010s
?       github.com/fluxcd/flux/pkg/http/client  [no test files]
ok      github.com/fluxcd/flux/pkg/http/daemon  0.107s
?       github.com/fluxcd/flux/pkg/http/httperror       [no test files]
ok      github.com/fluxcd/flux/pkg/http/websocket       0.073s
ok      github.com/fluxcd/flux/pkg/image        0.027s
ok      github.com/fluxcd/flux/pkg/job  0.063s
ok      github.com/fluxcd/flux/pkg/manifests    12.363s
?       github.com/fluxcd/flux/pkg/metrics      [no test files]
ok      github.com/fluxcd/flux/pkg/policy       0.011s
ok      github.com/fluxcd/flux/pkg/registry     0.067s
ok      github.com/fluxcd/flux/pkg/registry/cache       0.288s
?       github.com/fluxcd/flux/pkg/registry/cache/memcached     [no test files]
?       github.com/fluxcd/flux/pkg/registry/middleware  [no test files]
?       github.com/fluxcd/flux/pkg/registry/mock        [no test files]
ok      github.com/fluxcd/flux/pkg/release      35.445s
ok      github.com/fluxcd/flux/pkg/remote       0.216s
ok      github.com/fluxcd/flux/pkg/remote/rpc   0.049s
ok      github.com/fluxcd/flux/pkg/resource     0.037s
?       github.com/fluxcd/flux/pkg/ssh  [no test files]
ok      github.com/fluxcd/flux/pkg/sync 1.152s
ok      github.com/fluxcd/flux/pkg/update       0.025s

[2opremio]

Yeah, tests passed, I have too easy a trigger