use timeout in connect function to prevent against (#26364)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26364
Per https://github.com/pytorch/pytorch/issues/25769, we sometimes get
an infinite loop when `TCPStore` calls `tcputil::connect`, and the server
continually returns `ECONNRESET` or `ECONNREFUSED`. If a proper timeout is passed
in, we guard against this by throwing an exception once the timeout has passed.
Testing: Tested with modifying `TCPStore` to connect to an invalid port, thus getting
`ECONNREFUSED`. If a valid timeout is passed in, the function correctly throws an
exception. Steps below:
1) in TCPStore.cpp's constructor, replace the `connect` call with this line:
`storeSocket_ = tcputil::connect(tcpStoreAddr_, 1, true, std::chrono::milliseconds(3000));`
2) Build the `TCPStoreTest` binary.
3) Run the binary. Expected output:
```
terminate called after throwing an instance of 'std::runtime_error'
what(): Connecting to TCP store timed out.
Aborted (core dumped)
```
ghstack-source-id: 90480086
Test Plan: See above.
Differential Revision: D17430164
fbshipit-source-id: 1482aca72fcc3ddb95ea25649ec057edda5d1934
