Implement api-key's apis for web client

[nghialv]

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #1145

Does this PR introduce a user-facing change?:

NONE

[pipecd-bot]

Code coverage for golang is 33.26%. This pull request increases coverage by 0.07%.

File	Function	Base	Head	Diff
pkg/datastore/apikey.go	NewAPIKeyStore	--	100.00%	+100.00%
pkg/datastore/apikey.go	apiKeyStore.AddAPIKey	--	100.00%	+100.00%
pkg/datastore/apikey.go	apiKeyStore.ListAPIKeys	--	84.62%	+84.62%
pkg/datastore/apikey.go	apiKeyStore.DisableAPIKey	--	0.00%	+0.00%
pkg/model/apikey.go	GenerateAPIKey	--	87.50%	+87.50%
pkg/model/apikey.go	ExtractAPIKeyID	--	66.67%	+66.67%
pkg/model/apikey.go	APIKey.CompareKey	--	60.00%	+60.00%
pkg/model/apikey.go	APIKey.RedactSensitiveData	--	100.00%	+100.00%
pkg/model/model.go	GenerateRandomString	--	100.00%	+100.00%
pkg/app/api/grpcapi/web_api.go	WebAPI.GenerateAPIKey	0.00%	0.00%	+0.00%
pkg/app/api/grpcapi/web_api.go	WebAPI.DisableAPIKey	0.00%	0.00%	+0.00%
pkg/app/api/grpcapi/web_api.go	WebAPI.ListAPIKeys	0.00%	0.00%	+0.00%
pkg/model/piped.go	GenerateRandomString	100.00%	--	-100.00%

[nakabonne]

Looks good
/approve

[pipecd-bot]

This pull request is APPROVED by nakabonne.

Approvers can cancel the approval by writing /approve cancel in a comment. Any additional commits also will change this pull request to be not-approved.