test: 修复 firefox 测试兼容问题

pages/directive/v-bind/v-bind-style.test.js

 const PAGE_PATH = '/pages/directive/v-bind/v-bind-style'
 
 describe('v-bind-style', () => {
+  const isFirefox = process.env.uniTestPlatformInfo.indexOf('firefox') > -1
   let page
   beforeAll(async () => {
     page = await program.reLaunch(PAGE_PATH)
@@ -16,9 +17,9 @@ describe('v-bind-style', () => {
     } else {
       expect(await view.style('backgroundColor')).toBe('#008000')
     }
-    expect(await view.style('borderWidth')).toBe('2px')
-    if(process.env.uniTestPlatformInfo.startsWith('web')) {
-      expect(await view.style('borderColor')).toBe('rgb(0, 0, 255)')
+    expect(await view.style(isFirefox ? 'borderTopWidth' : 'borderWidth')).toBe('2px')
+    if (process.env.uniTestPlatformInfo.startsWith('web')) {
+      expect(await view.style(isFirefox ? 'borderTopColor' : 'borderColor')).toBe('rgb(0, 0, 255)')
     } else {
       expect(await view.style('borderColor')).toBe('#0000FF')
     }