Already included file name 'e:/08_study/vscode_project/Forward/20_Vue-cli/testcli/proj/src/components/Left.vue' differs from file name 'e:/08_study/vscode_project/Forward/20_Vue-cli/testcli/proj/src/components/left.vue' only in casing.
 The file is in the program because:
   Root file specified for compilation
   Imported via '../components/Left.vue' from file 'e:/08_study/vscode_project/Forward/20_Vue-cli/testcli/proj/src/views/First.vue'
   Root file specified for compilationVetur(1261)

请问这个为什么呀