doc: Update libnatpmp info in dependencies.md

Author: hebasto

doc/dependencies.md

@@ -14,7 +14,7 @@ These are the dependencies currently used by Bitcoin Core. You can find instruct
 | GCC |  | [7+](https://gcc.gnu.org/) (C++17 support) |  |  |  |
 | HarfBuzz-NG |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk) |
 | libevent | [2.1.11-stable](https://github.com/libevent/libevent/releases) | [2.0.21](https://github.com/bitcoin/bitcoin/pull/18676) | No |  |  |
-| libnatpmp | [20150609](https://miniupnp.tuxfamily.org/files) |  | No |  |  |
+| libnatpmp | git commit [4536032...](https://github.com/miniupnp/libnatpmp/tree/4536032ae32268a45c073a4d5e91bbab4534773a) |  | No |  |  |
 | libpng |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk) |
 | librsvg | |  |  |  |  |
 | MiniUPnPc | [2.0.20180203](https://miniupnp.tuxfamily.org/files) |  | No |  |  |