fix: #957 add . a readiness and heath probe

[chirino]

Thinking something like this might fix #957

But I'm not a bazel user.. build fails with:

compilepkg: missing strict dependencies:
	/home/chirino/.cache/bazel/_bazel_chirino/da5a820a69fa786d5aef66a3a74e00bd/sandbox/linux-sandbox/77/execroot/com_github_coachroachdb_cockroach_operator/cmd/cockroach-operator/main.go: import of "sigs.k8s.io/controller-runtime/pkg/healthz"
No dependencies were provided.

[cockroach-teamcity]

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