Set spdlog submodule branch to "master" explicitly. (#4087)
Set spdlog submodule branch to "master" explicitly. (#4087)

The default branch for the spdlog repository on GitHub recently changed from "master"
to "v1.x", which has a different API for `syslog_sink::syslog_sink()`. This breaks
builds of the server for anyone who has checked out the submodules since that change.

Fixes #4077.

Co-authored-by: Derek Murray <5363ef299151267de587053d3447f577b7e8aa2a@microsoft.com>
microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime,microsoft/onnxruntime