npm run watch-server fails on Windows

[provide a description of the issue]

Environment

• Operating System: Windows
• JDK version: 11
• Visual Studio Code version: 1.56.2
• Java extension version: v0.79.2

Steps To Reproduce

1. git clone https://github.com/redhat-developer/vscode-java.git
2. cd vscode-java
3. npm run watch-server

I get result:

> java@0.80.0 watch-server
> ./node_modules/.bin/gulp watch_server 
'.' is not recognized as an internal or external command,
operable program or batch file. 

Running a full path command like
cmd /c c:/dev/temp/vscode-java/node_modules/.bin/gulp dev_server
gives:

C:\Dev\temp\vscode-java>cmd /c c:/dev/temp/vscode-java/node_modules/.bin/gulp dev_server 
[18:28:27] Using gulpfile C:\Dev\temp\vscode-java\gulpfile.js
[18:28:28] Starting 'dev_server'...
executing mvnw.cmd -Pserver-distro,fast -o clean package -Denvironment.os=win32 -Denvironment.ws=win32 -Denvironment.arch=x86_64
[18:28:28] 'dev_server' errored after 7.28 ms
[18:28:28] Error: spawnSync C:\WINDOWS\system32\cmd.exe ENOENT
at Object.spawnSync (internal/child_process.js:1070:20)
at spawnSync (child_process.js:597:24)
at Object.execSync (child_process.js:642:15)
at C:\Dev\temp\vscode-java\gulpfile.js:41:5
at dev_server (C:\Dev\temp\vscode-java\node_modules\undertaker\lib\set-task.js:13:15)
at bound (domain.js:429:14)
at runBound (domain.js:442:12)
at asyncRunner (C:\Dev\temp\vscode-java\node_modules\async-done\index.js:55:18)
at processTicksAndRejections (internal/process/task_queues.js:79:11) 

I know I can do it all manually, just to let you know

首先在 Windows 上运行 npm run watch-server，并检查 gulpfile.js 中的 watch_server 任务，该任务的命令调用会失败。跟踪错误输出中显示的 Windows 命令处理过程，并验证 watch-server 工作流是否能够成功完成，且不再出现报告中的可执行文件或 cmd.exe 错误。