adding missingt test in context package

internal/app/xhttp/pkg/context/context_test.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/thecodingmachine/gotenberg/internal/pkg/conf"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/pm2"
 	"github.com/thecodingmachine/gotenberg/test"
 )
 
@@ -26,6 +27,27 @@ func TestMustCastFromEchoContext(t *testing.T) {
 	})
 }
 
+func TestProcessesHealthcheck(t *testing.T) {
+	// process is viable.
+	ctx := New(
+		test.DummyEchoContext(),
+		test.DebugLogger(),
+		conf.DefaultConfig(),
+		pm2.NewDummyProcess(true),
+	)
+	err := ctx.ProcessesHealthcheck()
+	assert.Nil(t, err)
+	// process is not viable.
+	ctx = New(
+		test.DummyEchoContext(),
+		test.DebugLogger(),
+		conf.DefaultConfig(),
+		pm2.NewDummyProcess(false),
+	)
+	err = ctx.ProcessesHealthcheck()
+	test.AssertError(t, err)
+}
+
 func TestLogRequestResult(t *testing.T) {
 	ctx := New(
 		test.DummyEchoContext(),