chore: remove all remaining uses of golang.org/x/net/context (#47564)

* chore: remove all remaining uses of  golang.org/x/net/context

This PR finishes the work started in #47532, replacing all calls to that package with the stdlib context and using http.NewRequestWithContext to include the context where necessary.

Bonus: small formatting fixes to goimports in these files.

closes #44178

* tweak: use context.Background in favor of TODO for tests

pkg/tsdb/azuremonitor/loganalytics/azure-log-analytics-datasource.go

@@ -15,14 +15,14 @@ import (
 
 	"github.com/grafana/grafana-plugin-sdk-go/backend"
 	"github.com/grafana/grafana-plugin-sdk-go/data"
+	"go.opentelemetry.io/otel/attribute"
+
 	"github.com/grafana/grafana/pkg/components/simplejson"
 	"github.com/grafana/grafana/pkg/infra/tracing"
 	"github.com/grafana/grafana/pkg/tsdb/azuremonitor/azlog"
 	"github.com/grafana/grafana/pkg/tsdb/azuremonitor/macros"
 	"github.com/grafana/grafana/pkg/tsdb/azuremonitor/types"
 	"github.com/grafana/grafana/pkg/util/errutil"
-	"go.opentelemetry.io/otel/attribute"
-	"golang.org/x/net/context/ctxhttp"
 )
 
 // AzureLogAnalyticsDatasource calls the Azure Log Analytics API's
@@ -173,7 +173,7 @@ func (e *AzureLogAnalyticsDatasource) executeQuery(ctx context.Context, query *A
 	tracer.Inject(ctx, req.Header, span)
 
 	azlog.Debug("AzureLogAnalytics", "Request ApiURL", req.URL.String())
-	res, err := ctxhttp.Do(ctx, client, req)
+	res, err := client.Do(req)
 	if err != nil {
 		return dataResponseErrorWithExecuted(err)
 	}
@@ -224,7 +224,7 @@ func (e *AzureLogAnalyticsDatasource) executeQuery(ctx context.Context, query *A
 }
 
 func (e *AzureLogAnalyticsDatasource) createRequest(ctx context.Context, dsInfo types.DatasourceInfo, url string) (*http.Request, error) {
-	req, err := http.NewRequest(http.MethodGet, url, nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
 	if err != nil {
 		azlog.Debug("Failed to create request", "error", err)
 		return nil, errutil.Wrap("failed to create request", err)