depends: xcb-proto 1.15.2

Resolves build failures under Python 3.12, i.e building on rawhide:
```bash
make[3]: Nothing to be done for 'install-exec-am'.
 /usr/bin/mkdir -p '/bitcoin/depends/work/staging/aarch64-unknown-linux-gnu/xcb_proto/1.14.1-4a91ac9dc41/bitcoin/depends/aarch64-unknown-linux-gnu/lib/python3.12/site-packages/xcbgen'
 /usr/bin/install -c -m 644 __init__.py error.py expr.py align.py matcher.py state.py xtypes.py '/bitcoin/depends/work/staging/aarch64-unknown-linux-gnu/xcb_proto/1.14.1-4a91ac9dc41/bitcoin/depends/aarch64-unknown-linux-gnu/lib/python3.12/site-packages/xcbgen'
Traceback (most recent call last):
  File "<string>", line 2, in <module>
ModuleNotFoundError: No module named 'imp'
make[3]: *** [Makefile:271: install-pkgpythonPYTHON] Error 1
```

`imp` was removed in 3.12: https://docs.python.org/3/library/imp.html.

depends/packages/xcb_proto.mk

@@ -1,8 +1,8 @@
 package=xcb_proto
-$(package)_version=1.14.1
+$(package)_version=1.15.2
 $(package)_download_path=https://xorg.freedesktop.org/archive/individual/proto
 $(package)_file_name=xcb-proto-$($(package)_version).tar.xz
-$(package)_sha256_hash=f04add9a972ac334ea11d9d7eb4fc7f8883835da3e4859c9afa971efdf57fcc3
+$(package)_sha256_hash=7072beb1f680a2fe3f9e535b797c146d22528990c72f63ddb49d2f350a3653ed
 
 define $(package)_config_cmds
   $($(package)_autoconf)