refactor: drop qEnvironmentVariableIsSet conditional compile

since Qt5.15 needed

Author: CoelacanthusHex

makespec/BUILDVERSION

@@ -1 +1 @@
-126
+127

src/base/LemonBase.hpp

@@ -44,16 +44,12 @@ namespace Lemon {
 		//
 		list << makeAbs("/usr/share/lemon-lime/" + dirName);
 		list << makeAbs("/usr/local/share/lemon-lime/" + dirName);
-		// For AppImage?
-		list << makeAbs(QCoreApplication::applicationDirPath() + "/../share/lemon-lime/" + dirName);
 		// For Snap
-#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
 		if (qEnvironmentVariableIsSet("SNAP")) {
 			list << makeAbs(qEnvironmentVariable("SNAP") + "/usr/share/lemon-lime/" + dirName);
 		}
 		if (qEnvironmentVariableIsSet("APPIMAGE"))
 			list << makeAbs(QCoreApplication::applicationDirPath() + "/../share/lemon-lime/" + dirName);
-#endif
 #elif defined(Q_OS_MAC)
 		// macOS platform directories.
 		list << QDir(QCoreApplication::applicationDirPath() + "/../Resources/" + dirName).absolutePath();