Wrong `framerate()` of webcam

[chunjiw]

cam = opencamera()
VideoIO.framerate(cam)

gives 1//0. The webcam works normally.

Julia Version 1.7.3
Commit 742b9abb4d (2022-05-06 12:58 UTC)
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-12.0.1 (ORCJIT, skylake)

[IanButterworth]

Seems similar to https://github.com/JuliaIO/VideoIO.jl/issues/349

[chunjiw]

Yeah, it is a similar issue, but the workaround in #349 does not work for webcam.