Add test for error problemMatcher

For eng/ide/ada_language_server#1723

Author: AnthonyLeonardoGracio

integration/vscode/ada/test/general/tasks.test.ts

@@ -388,6 +388,20 @@ ada: Run main - src/test.adb - .${path.sep}obj${path.sep}test${exe}
 1: function "Get_Or_Create_Manager" is not referenced [-gnatwu]`.trim(),
         );
     });
+
+    test('problemMatchers severities (errors only)', async () => {
+        await testProblemMatchersWithCompilerMessages(
+            'compiler_messages_errors_only.txt',
+            `
+0: "New_Var_Edit" is undefined (more references follow)
+0: no candidate interpretations match the actuals:
+0: unmatched actual "Title" in call
+0: "Update_Variable" is undefined (more references follow)
+0: no candidate interpretations match the actuals:
+0: found type "Kernel_Handle" defined at gps-kernel.ads:92
+0: expected type "Standard.Boolean"`.trim(),
+        );
+    });
 });
 
 suite('Task Execution', function () {

integration/vscode/ada/test/general/ws/main_with_problem/compiler_messages_errors_only.txt

@@ -0,0 +1,25 @@
+/home/unknown/src/scenario_views.adb:774:18: error: "New_Var_Edit" is undefined (more references follow)
+/home/unknown/src/scenario_views.adb:776:07: error: no candidate interpretations match the actuals:
+/home/unknown/src/scenario_views.adb:776:07: error: missing argument for parameter "Kernel" in call to "Gtk_New" declared at gps-kernel-mdi.ads:147
+/home/unknown/src/scenario_views.adb:776:07: error: missing argument for parameter "Group" in call to "Gtk_New" declared at gps-kernel-mdi.ads:116
+/home/unknown/src/scenario_views.adb:776:07: error: missing argument for parameter "Home_Dir" in call to "Gtk_New" declared at gps-kernel.ads:100
+/home/unknown/src/scenario_views.adb:776:07: error: missing argument for parameter "Flags" in call to "Gtk_New" declared at gtk-message_dialog.ads:124
+/home/unknown/src/scenario_views.adb:776:07: error: missing argument for parameter "Flags" in call to "Gtk_New" declared at gtk-dialog.ads:223
+/home/unknown/src/scenario_views.adb:776:07: error: too many arguments in call to "Gtk_New"
+/home/unknown/src/scenario_views.adb:776:07: error: missing argument for parameter "Spacing" in call to "Gtk_New" declared at gtk-box.ads:107
+/home/unknown/src/scenario_views.adb:777:16: error: unmatched actual "Title" in call
+/home/unknown/src/scenario_views.adb:781:22: error: "Update_Variable" is undefined (more references follow)
+/home/unknown/src/scenario_views.adb:854:10: error: no candidate interpretations match the actuals:
+/home/unknown/src/scenario_views.adb:854:10: error: missing argument for parameter "Log_Dir" in call to "Gtk_New" declared at gps-kernel.ads:100
+/home/unknown/src/scenario_views.adb:854:10: error: missing argument for parameter "Buttons" in call to "Gtk_New" declared at gtk-message_dialog.ads:124
+/home/unknown/src/scenario_views.adb:854:10: error: too many arguments in call to "Gtk_New"
+/home/unknown/src/scenario_views.adb:854:26: error: found type "Kernel_Handle" defined at gps-kernel.ads:92
+/home/unknown/src/scenario_views.adb:854:26: error:   ==> in call to "Gtk_New" at gps-kernel-mdi.ads:147
+/home/unknown/src/scenario_views.adb:854:26: error: expected an access type with designated type "Gtk_Widget_Record'Class" defined at gtk-widget.ads:350
+/home/unknown/src/scenario_views.adb:854:26: error: found type "Kernel_Handle" defined at gps-kernel.ads:92
+/home/unknown/src/scenario_views.adb:854:26: error:   ==> in call to "Gtk_New" at gtkada-mdi.ads:251
+/home/unknown/src/scenario_views.adb:854:26: error: expected type "UTF8_String" defined at glib.ads:79
+/home/unknown/src/scenario_views.adb:854:26: error: found type "Kernel_Handle" defined at gps-kernel.ads:92
+/home/unknown/src/scenario_views.adb:854:26: error:   ==> in call to "Gtk_New" at gtk-dialog.ads:223
+/home/unknown/src/scenario_views.adb:857:21: error: expected type "Standard.Boolean"
+/home/unknown/src/scenario_views.adb:857:21: error: found type "Action_Filter" defined at gps-kernel.ads:458