[BUGFIX] SLD : Support escapeChar attribute of PropertyIsLike

In OGC FilterEncoding standard, the PropertyIsLike element has an escapeChar attribute in place of escape attribute.

In the QgsOgcUtils class, the attribute escape or escapeChar is added to PropertyIsLike element, but it only checks escape attribute when it decodes it.

The commit fixed it and adds test.

src/core/qgsogcutils.cpp

@@ -1808,6 +1808,10 @@ QgsExpression::NodeBinaryOperator* QgsOgcUtils::nodeBinaryOperatorFromOgcFilter(
       {
         escape = element.attribute( "escape" );
       }
+      else if ( element.hasAttribute( "escapeChar" ) )
+      {
+        escape = element.attribute( "escapeChar" );
+      }
       // replace
       QString oprValue = static_cast<const QgsExpression::NodeLiteral*>( opRight )->value().toString();
       if ( !wildCard.isEmpty() && wildCard != "%" )

tests/src/core/testqgsogcutils.cpp

@@ -330,13 +330,19 @@ void TestQgsOgcUtils::testExpressionFromOgcFilter_data()
     "<PropertyName>NAME</PropertyName><Literal>._QGIS.\\.</Literal></PropertyIsLike>"
     "</Filter>" )
   << QString( "NAME LIKE '_\\\\_QGIS_.'" );
-  // different single chars
+  // different escape chars
   QTest::newRow( "like escape char" ) << QString(
     "<Filter>"
     "<PropertyIsLike wildCard=\"*\" singleChar=\".\" escape=\"!\">"
     "<PropertyName>NAME</PropertyName><Literal>_QGIS.!.!!%QGIS*!*</Literal></PropertyIsLike>"
     "</Filter>" )
   << QString( "NAME LIKE '\\\\_QGIS_.!\\\\%QGIS%*'" );
+  QTest::newRow( "like escape char" ) << QString(
+    "<Filter>"
+    "<PropertyIsLike wildCard=\"*\" singleChar=\".\" escapeChar=\"!\">"
+    "<PropertyName>NAME</PropertyName><Literal>_QGIS.!.!!%QGIS*!*</Literal></PropertyIsLike>"
+    "</Filter>" )
+  << QString( "NAME LIKE '\\\\_QGIS_.!\\\\%QGIS%*'" );
 
   QTest::newRow( "is null" ) << QString(
     "<Filter>"