[receiver/snowflake] Enable component

[shalper2]

Description: Graduate snowflakereceiver component to Alpha

Link to tracking Issue: 21381

Testing: Ran make otelcontribcol and ran command with the following config:

receivers:
  snowflake:
    username: snowflakeuser
    password: securepassword
    account: bigbusinessaccount
    warehouse: metricWarehouse

exporters:
  logging:

service:
  pipelines:
    metrics:
      receivers: [snowflake]
      exporters: [logging]

and received the following output:

./opentelemetry-collector-contrib/bin/otelcontribcol_darwin_amd64 --config=file:config.yaml
2023-05-03T09:01:44.738-0500	info	service/telemetry.go:115	Setting up own telemetry...
2023-05-03T09:01:44.738-0500	info	service/telemetry.go:172	Serving Prometheus metrics	{"address": ":8888", "level": "Basic"}
2023-05-03T09:01:44.738-0500	info	[email protected]/exporter.go:286	Development component. May change in the future.	{"kind": "exporter", "data_type": "metrics", "name": "logging"}
2023-05-03T09:01:44.738-0500	info	[email protected]/receiver.go:307	Development component. May change in the future.	{"kind": "receiver", "name": "snowflake", "data_type": "metrics"}
2023-05-03T09:01:44.739-0500	info	service/service.go:130	Starting otelcontribcol...	{"Version": "0.76.3-dev", "NumCPU": 12}
2023-05-03T09:01:44.739-0500	info	extensions/extensions.go:41	Starting extensions...
2023-05-03T09:01:44.739-0500	info	service/service.go:147	Everything is ready. Begin running and processing data.

indicating that the component was successfully added to the collector.