Remove support for Google Spanner database. (#105846)

* Remove support for Google Spanner database.

go.mod

@@ -6,7 +6,6 @@ require (
 	buf.build/gen/go/parca-dev/parca/connectrpc/go v1.17.0-20240902100956-02fd72488966.1 // @grafana/observability-traces-and-profiling
 	buf.build/gen/go/parca-dev/parca/protocolbuffers/go v1.34.2-20240902100956-02fd72488966.2 // @grafana/observability-traces-and-profiling
 	cloud.google.com/go/kms v1.20.5 // @grafana/grafana-backend-group
-	cloud.google.com/go/spanner v1.75.0 // @grafana/grafana-search-and-storage
 	cloud.google.com/go/storage v1.50.0 // @grafana/grafana-backend-group
 	connectrpc.com/connect v1.17.0 // @grafana/observability-traces-and-profiling
 	cuelang.org/go v0.11.1 // @grafana/grafana-as-code
@@ -75,7 +74,6 @@ require (
 	github.com/google/uuid v1.6.0 // @grafana/grafana-backend-group
 	github.com/google/wire v0.6.0 // @grafana/grafana-backend-group
 	github.com/googleapis/gax-go/v2 v2.14.1 // @grafana/grafana-backend-group
-	github.com/googleapis/go-sql-spanner v1.11.1 // @grafana/grafana-search-and-storage
 	github.com/gorilla/mux v1.8.1 // @grafana/grafana-backend-group
 	github.com/gorilla/websocket v1.5.4-0.20250319132907-e064f32e3674 // @grafana/grafana-app-platform-squad
 	github.com/grafana/alerting v0.0.0-20250521131632-6e476b0b04c3 // @grafana/alerting-backend
@@ -253,7 +251,6 @@ require (
 	github.com/Azure/go-ntlmssp v0.0.0-20220621081337-cb9428e4ac1e // indirect
 	github.com/AzureAD/microsoft-authentication-library-for-go v1.3.2 // indirect
 	github.com/FZambia/eagle v0.2.0 // indirect
-	github.com/GoogleCloudPlatform/grpc-gcp-go/grpcgcp v1.5.2 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.26.0 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric v0.49.0 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping v0.49.0 // indirect