Current GDB/MI link gives an HTTP 404 error.
Also, this fixes a small typo.
# Debugger for .NET Core runtime
-The debugger provides [GDB/MI](https://sourceware.org/gdb/current/onlinedocs/gdb/GDB_002fMI.html)
-and [VSCode Debug Adapterprotocol](https://microsoft.github.io/debug-adapter-protocol/)
+The debugger provides [GDB/MI](https://sourceware.org/gdb/onlinedocs/gdb/GDB_002fMI.html)
+and [VSCode Debug Adapter Protocol](https://microsoft.github.io/debug-adapter-protocol/)
and allows to debug .NET apps under .NET Core runtime. Also debugger allows debugging from
command line (like as GDB).