Meson: Skip tests if meson is not installed

Change-Id: I118e687ff69c264e64e8a018ef6aa131f26463c6
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>

src/plugins/mesonprojectmanager/tests/testmesoninfoparser.cpp

@@ -88,6 +88,10 @@ private slots:
                                                                + "/mesontest-XXXXXX");
         Utils::LauncherInterface::setPathToLauncher(qApp->applicationDirPath() + '/'
                                                     + QLatin1String(TEST_RELATIVE_LIBEXEC_PATH));
+
+        const auto path = MesonWrapper::find();
+        if (!path)
+            QSKIP("Meson not found");
     }
 
     void shouldListTargets_data()

src/plugins/mesonprojectmanager/tests/testmesonwrapper.cpp

@@ -55,6 +55,10 @@ private slots:
                                                                + "/mesontest-XXXXXX");
         Utils::LauncherInterface::setPathToLauncher(qApp->applicationDirPath() + '/'
                                                     + QLatin1String(TEST_RELATIVE_LIBEXEC_PATH));
+
+        const auto path = MesonWrapper::find();
+        if (!path)
+            QSKIP("Meson not found");
     }
 
     void shouldFindMesonFromPATH()