fix: Use unicode arrows in quadrant chart axis

packages/mermaid/src/diagrams/quadrant-chart/parser/quadrant.jison

@@ -119,10 +119,10 @@ points
 
 axisDetails
   : X-AXIS text AXIS-TEXT-DELIMITER text {yy.setXAxisLeftText($2); yy.setXAxisRightText($4);}
-  | X-AXIS text AXIS-TEXT-DELIMITER {$2.text += $3; yy.setXAxisLeftText($2);}
+  | X-AXIS text AXIS-TEXT-DELIMITER {$2.text += " ⟶ "; yy.setXAxisLeftText($2);}
   | X-AXIS text {yy.setXAxisLeftText($2);}
   | Y-AXIS text AXIS-TEXT-DELIMITER text {yy.setYAxisBottomText($2); yy.setYAxisTopText($4);}
-  | Y-AXIS text AXIS-TEXT-DELIMITER {$2.text += $3; yy.setYAxisBottomText($2);}
+  | Y-AXIS text AXIS-TEXT-DELIMITER {$2.text += " ⟶ "; yy.setYAxisBottomText($2);}
   | Y-AXIS text {yy.setYAxisBottomText($2);}
   ;
 

packages/mermaid/src/diagrams/quadrant-chart/parser/quadrant.jison.spec.ts

@@ -93,7 +93,7 @@ describe('Testing quadrantChart jison file', () => {
     str = 'quadrantChart\n       x-AxIs         "Urgent(* +=[❤"  --> ';
     expect(parserFnConstructor(str)).not.toThrow();
     expect(mockDB.setXAxisLeftText).toHaveBeenCalledWith({
-      text: 'Urgent(* +=[❤  --> ',
+      text: 'Urgent(* +=[❤ ⟶ ',
       type: 'text',
     });
     expect(mockDB.setXAxisRightText).not.toHaveBeenCalled();
@@ -131,7 +131,7 @@ describe('Testing quadrantChart jison file', () => {
     str = 'quadrantChart\n       y-AxIs         "Urgent(* +=[❤"  --> ';
     expect(parserFnConstructor(str)).not.toThrow();
     expect(mockDB.setYAxisBottomText).toHaveBeenCalledWith({
-      text: 'Urgent(* +=[❤  --> ',
+      text: 'Urgent(* +=[❤ ⟶ ',
       type: 'text',
     });
     expect(mockDB.setYAxisTopText).not.toHaveBeenCalled();