Instrumentation: log the total number of db queries per request (#54647)

Signed-off-by: bergquist <carl.bergquist@gmail.com>
Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>
Co-authored-by: Dave Henderson <dave.henderson@grafana.com>

pkg/infra/log/databaseCounter_test.go

@@ -0,0 +1,19 @@
+package log
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCountingDatabaseCalls(t *testing.T) {
+	ctx := context.Background()
+
+	ctx = IncDBCallCounter(ctx)
+	ctx = IncDBCallCounter(ctx)
+	ctx = IncDBCallCounter(ctx)
+
+	count := TotalDBCallCount(ctx)
+	assert.Equal(t, int64(3), count, "expect counter to increase three times")
+}