[cosigned] Rename cosigned references to policy-controller

[hectorj2f]

Summary

This PR renames all the references of cosigned to policy-controller, as decided in sigstore/TSC#9 and discussed in #1892.

Ticket Link

Fixes #1892

Release Note

cosigned: rename cosigned references to its new name policy-controller.

[adamd-vmw]

Thank you @hectorj2f and @imjasonh !

[codecov-commenter]

Codecov Report

Merging #1893 (a98b0b2) into main (4a9a642) will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##             main    #1893   +/-   ##
=======================================
  Coverage   34.03%   34.03%           
=======================================
  Files         153      153           
  Lines        9934     9934           
=======================================
  Hits         3381     3381           
  Misses       6173     6173           
  Partials      380      380           

Impacted Files	Coverage Δ
cmd/cosign/policy_webhook/main.go	0.00% <0.00%> (ø)
cmd/cosign/webhook/main.go	0.00% <0.00%> (ø)
...s/policy/v1alpha1/clusterimagepolicy_conversion.go	79.41% <ø> (ø)
...pis/policy/v1alpha1/clusterimagepolicy_defaults.go	100.00% <ø> (ø)
...g/apis/policy/v1alpha1/clusterimagepolicy_types.go	0.00% <ø> (ø)
...s/policy/v1alpha1/clusterimagepolicy_validation.go	93.75% <ø> (ø)
pkg/apis/policy/v1alpha1/register.go	0.00% <ø> (ø)
pkg/apis/policy/v1alpha1/zz_generated.deepcopy.go	0.00% <ø> (ø)
...is/policy/v1beta1/clusterimagepolicy_conversion.go	100.00% <ø> (ø)
...apis/policy/v1beta1/clusterimagepolicy_defaults.go	100.00% <ø> (ø)
... and 7 more

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[dlorenc]

This looks good but has a small merge conflict still.

[coyote240]

On find/replace error, otherwise as good as I can anticipate.