fix(boards): 修复xpython下变量名大小写不敏感

boards/default_src/python/blocks/variables.js

@@ -214,18 +214,15 @@ export const lists_zip = {
         this.setMutator(new Blockly.icons.MutatorIcon(['lists_zip_item'], this));
         this.setTooltip(Blockly.Msg.MIXLY_PYTHON_LISTS_ZIP_TOOLTIP);
     },
-
     mutationToDom: function () {
         var container = document.createElement('mutation');
         container.setAttribute('items', this.itemCount_);
         return container;
     },
-
     domToMutation: function (xmlElement) {
         this.itemCount_ = parseInt(xmlElement.getAttribute('items'), 10);
         this.updateShape_();
     },
-
     decompose: function (workspace) {
         var containerBlock =
             workspace.newBlock('lists_zip_container');
@@ -239,7 +236,6 @@ export const lists_zip = {
         }
         return containerBlock;
     },
-
     compose: function (containerBlock) {
         var itemBlock = containerBlock.getInputTargetBlock('STACK');
         // Count number of inputs.
@@ -260,7 +256,6 @@ export const lists_zip = {
             }
         }
     },
-
     saveConnections: function (containerBlock) {
         var itemBlock = containerBlock.getInputTargetBlock('STACK');
         var i = 0;
@@ -272,7 +267,6 @@ export const lists_zip = {
                 itemBlock.nextConnection.targetBlock();
         }
     },
-
     updateShape_: function () {
         // Delete everything.
         if (this.getInput('EMPTY')) {