correctly close files executed from QgsPythonRunner

src/app/main.cpp

@@ -1386,7 +1386,7 @@ int main( int argc, char *argv[] )
     //replace backslashes with forward slashes
     pythonfile.replace( '\\', '/' );
 #endif
-    QgsPythonRunner::run( QStringLiteral( "exec(open('%1').read())" ).arg( pythonfile ) );
+    QgsPythonRunner::run( QStringLiteral( "with open('%1','r') as f: exec(f.read())" ).arg( pythonfile ) );
   }
 
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