unreliable test: 'mkdir ... creates folder but uses the "fs" module if in C9'

[justinmk3]

test failure sometimes occurs:

  1) FileSystem
       mkdir()
         creates folder but uses the "fs" module if in C9: 'a':

      AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:

  assert_1.default.ok(mkdirSpy.calledOnce)

      + expected - actual

      -false
      +true
      
      at Context.<anonymous> (d:\a\aws-toolkit-vscode\aws-toolkit-vscode\src\test\srcShared\fs.test.ts:177:24)

[nkomonen-amazon]

Looking

[justinmk3]

Similar case is present on latest master:

  1 failing
  1) FileSystem
       mkdir()
         creates folder but uses the "fs" module if in C9: 'a/b/c':

      AssertionError [ERR_ASSERTION]: Expected values to be strictly equal:

2 !== 1

      + expected - actual

      -2
      +1
      
      at Context.<anonymous> (src/test/srcShared/fs.test.ts:179:24)