bazelisk --migrate failing on Windows in 1.7.2

[meteorcloudy]

https://buildkite.com/bazel/bazelisk-plus-incompatible-flags/builds/661#d29b31f2-3c63-4bdf-904c-801ec05e6117

I can reproduce the failure locally

pcloudy@PCLOUDY2-W MSYS ~/workspace/my_tests/bazel
$ bazelisk-windows-amd64.exe --migrate build examples/cpp:hello-world
2020/10/16 13:46:48 Downloading https://releases.bazel.build/3.6.0/release/bazel-3.6.0-windows-x86_64.exe...
2020/10/16 13:46:50 could not get the list of incompatible flags: invalid version unknown

@fweikert