test(e2e): reduce image assets (#2120)

Author: chenjiahan

e2e/cases/svg/svgr-default-export-url/src/small.svg renamed to e2e/assets/circle.svg

@@ -1,4 +1,4 @@
 .the-a-class {
   color: red;
-  background-image: url('@common/icon.png?url');
+  background-image: url('@assets/icon.png?url');
 }

e2e/cases/css/resolve-alias/src/common/icon.png renamed to e2e/assets/icon.png

@@ -1,4 +1,4 @@
 .the-b-class {
   color: blue;
-  background-image: url('@common/icon.png?url');
+  background-image: url('@assets/icon.png?url');
 }

e2e/cases/image-compress/src/image.ico renamed to e2e/assets/image.ico

@@ -1,4 +1,4 @@
 .the-c-class {
   color: yellow;
-  background-image: url('@common/icon.png?url');
+  background-image: url('@assets/icon.png?url');
 }

e2e/cases/image-compress/src/image.jpeg renamed to e2e/assets/image.jpeg

@@ -1,4 +1,4 @@
 .bar {
   color: blue;
-  background-image: url('./images/icon.png?url');
+  background-image: url('@assets/icon.png?url');
 }