Integration tests

Similar to https://github.com/grafana/loki/blob/main/integration we should add integrations test.

I suggest we start with adding push with all supported formats in both microservices and single binary mode.

Then once we have a good library we could extends to querying, and e2e benchmarking.

I also find https://github.com/efficientgo/e2e very cleanly designed but I don't want us to run docker images.

```[tasklist]
### Tasks
- [ ] Create a library for running integration tests without docker
- [ ] Add integration tests for connect go sdk push
- [ ] Add integration tests for all /ingest format
- [ ] Add integration tests for querying stacktraces
- [ ] Add integration tests for querying pprof
- [ ] Add integration tests for querying timeseries, series, labels etc...
```