fix(kuma-cp): disable statsForAllMethods in grpc stats

[jakubdyszkiewicz]

It does not make sense to use statsForAllMethods at this moment, because it's very common to use dots in grpc package which breaks the StatsD to Prometheus conversion.

There is a feature to replace dots with underscores, but Envoy with this feature is not yet released
https://www.envoyproxy.io/docs/envoy/latest/api-v3/extensions/filters/http/grpc_stats/v3/config.proto#envoy-v3-api-field-extensions-filters-http-grpc-stats-v3-filterconfig-stats-for-all-methods replace_dots_in_grpc_service_name.

If someone wants to still use it, they can reenable this with ProxyTemplate.
In the future, we can reenable this when Kuma will upgrade to Envoy with replace_dots_in_grpc_service_name feature.

Changes

• Disable statsForAllMethods
• Add E2E test to check if gRPC client and server emits stats
• Change the gRPC test client to be resilient to connection errors.

Checklist prior to review

• Link to docs PR or issue -- no extra docs.
• Link to UI issue or PR -- no
• Is the issue worked on linked? -- gRPC stats mapping is broken #5201
• The PR does not hardcode values that might break projects that depend on kuma (e.g. "kumahq" as a image registry) --
• The PR will work for both Linux and Windows, system specific functions like syscall.Mkfifo have equivalent implementation on the other OS --
• Unit Tests --
• E2E Tests --
• Manual Universal Tests --
• Manual Kubernetes Tests --
• Do you need to update UPGRADE.md? --
• Does it need to be backported according to the backporting policy? --
• Do you need to explicitly set a > Changelog: entry here or add a ci/ label to run fewer/more tests?

[lahabana]

I doubt anyone uses grpc stats as they are atm but I think it still makes sense to add a note in UPGRADE.md.