Make package paths referenced by import boss valid

[liggitt]

What type of PR is this?

/kind bug

What this PR does / why we need it:

verify-import-boss.sh references package paths of the form k8s.io/api/..., but many of the staging repos roots are not valid go packages.

This adds doc.go files to make them valid packages so that go package resolution works properly in gopath and go module mode.

Hoisted out of #99226. Prereq to #105299

Which issue(s) this PR fixes:

xref #82531

NONE

/area code-organization
/cc @dims

[fedebongio]

/remove-sig api-machinery

[dims]

/retest
/approve

[dims]

i can't see what's wrong with verify deps job @liggitt

+++ command: bash "hack/make-rules/../../hack/verify-vendor.sh"
+++ [0928 20:38:50] logfile at /tmp/update-vendor.cnWI/update-vendor.log
+++ [0928 20:38:50] go.mod: update staging references
+++ [0928 20:39:13] go.mod: propagate to staging modules
+++ [0928 20:39:14] go.mod: sorting staging modules
Removing /home/prow/go/src/k8s.io/kubernetes/_tmp/kube-vendor.8sbGiA
+++ exit code: 1
+++ error: 1
�[0;31mFAILED�[0m   verify-vendor.sh	32s
========================
�[0;31mFAILED TESTS�[0m
========================
�[0;31mhack/make-rules/../../hack/verify-vendor.sh�[0m
make: *** [Makefile:128: verify] Error 1
+ EXIT_VALUE=2
+ set +o xtrace
Cleaning up after docker in docker.

[k8s-triage-robot]

This PR may require API review.

If so, when the changes are ready, complete the pre-review checklist and request an API review.

Status of requested reviews is tracked in the API Review project.

[liggitt]

conflict in package declaration between a tools.go file already in k8s.io/code-generator:

=== computing tools imports for k8s.io/apiextensions-apiserver
go: found k8s.io/code-generator in k8s.io/code-generator v0.0.0-00010101000000-000000000000
examples/client-go/hack/tools.go:23:8: found packages codegenerator (doc.go) and tools (tools.go) in /Users/liggitt/go/src/k8s.io/kubernetes/staging/src/k8s.io/code-generator

fixed in latest push

[dims]

/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dims, liggitt

The full list of commands accepted by this bot can be found here.

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Needs approval from an approver in each of these files:

• staging/OWNERS [liggitt]
• staging/src/k8s.io/api/OWNERS [liggitt]
• staging/src/k8s.io/legacy-cloud-providers/OWNERS [dims,liggitt]

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[jpbetz]

/triage accepted

[eddiezane]

This PR seems to have broken the (probably incorrect) way I've been running tests.

make test WHAT=./staging/src/k8s.io/kubectl/...
+++ [1026 18:01:05] Running tests without code coverage and with -race
code in directory /home/eddiezane/Codez/kubernetes/kubernetes/_output/local/go/src/k8s.io/kubernetes/staging/src/k8s.io/kubectl expects import "k8s.io/kubectl"
make: *** [Makefile:184: test] Error 1

Anyone coming here from git bisect should use the sub pkg directory.

make test WHAT=./staging/src/k8s.io/kubectl/pkg/...
+++ [1026 18:01:39] Running tests without code coverage and with -race
?       k8s.io/kubernetes/staging/src/k8s.io/kubectl/pkg/apply  [no test files]
ok      k8s.io/kubernetes/staging/src/k8s.io/kubectl/pkg/apply/parse    0.040s