Symbol Fields Table: menu shortcut should start in edit tab

The BOM shortcut goes to Export, this makes them symmetrical.

eeschema/dialogs/dialog_symbol_fields_table.h

@@ -48,6 +48,7 @@ public:
     bool TransferDataToWindow() override;
     bool TransferDataFromWindow() override;
 
+    void ShowEditTab();
     void ShowExportTab();
 
 private:

eeschema/tools/sch_editor_control.cpp

@@ -2062,6 +2062,8 @@ int SCH_EDITOR_CONTROL::EditSymbolFields( const TOOL_EVENT& aEvent )
     // Bring it to the top if already open.  Dual monitor users need this.
     dlg->Raise();
 
+    dlg->ShowEditTab();
+
     return 0;
 }