🐛 clusterctl: move handlePlugins function call out of init to allow debugging tests

[chrischdi]

What this PR does / why we need it:

This PR moves the call to handlePlugins() from init() to Execute().

Calling handlePlugins() at the init function leads to not being able to debug tests using dlv, instead it exits with the following error message:

Error: flags cannot be placed before plugin name: -test.run

Reason for that is that the test execution will try to run a plugin because running tests provides args. At the end it always exits with an error and os.Exit(1) here:

cluster-api/cmd/clusterctl/cmd/root.go

Line 221 in 02b8789

os.Exit(1)

Moving the call to handlePlugins from the init function to Execute leads to not running it when running tests.

Found this while trying to investigate the following test:

cluster-api/cmd/clusterctl/cmd/config_repositories_test.go

Line 30 in 02b8789

func Test_runGetRepositories(t *testing.T) {

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

/area clusterctl

[chrischdi]

Note: clusterctl plugins still work:

❯ go run ./cmd/clusterctl foo
I'm the foo plugin

[fabriziopandini]

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 1ada872b79c59a06a70db0e19932d675e534dbac

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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