scripted-diff: Replace MilliSleep with UninterruptibleSleep

This is safe because MilliSleep is never executed in a boost::thread,
the only type of thread that is interruptible.

* The RPC server uses std::thread
* The wallet is either executed in an RPC thread or the main thread
* bitcoin-cli, benchmarks and tests are only one thread (the main thread)

-BEGIN VERIFY SCRIPT-
sed -i --regexp-extended -e 's/MilliSleep\((\S+)\);/UninterruptibleSleep(std::chrono::milliseconds{\1});/g' $(git grep -l MilliSleep)
-END VERIFY SCRIPT-

src/bitcoin-cli.cpp

@@ -524,7 +524,7 @@ static int CommandLineRPC(int argc, char *argv[])
             }
             catch (const CConnectionFailed&) {
                 if (fWait)
-                    MilliSleep(1000);
+                    UninterruptibleSleep(std::chrono::milliseconds{1000});
                 else
                     throw;
             }