Fix GoReleaser / Homebrew configuration

I previously set an incorrect Homebrew formula filename that caused
kube-capacity to not be released via Homebrew.

.goreleaser.yml

@@ -30,7 +30,7 @@ changelog:
     - '^docs:'
     - '^test:'
 brews:
-- name: homebrew-tap
+- name: kube-capacity
   tap:
     # The token determines the release type (Github/Gitlab).
     owner: robscott