Fix Windows workflow vcpkg pango checksum mismatch issue

[stackotter]

The Windows workflow started failing due to no fault of our own. The cause was vcpkg triggering Gitlab's bot screening page to appear (or at least mishandling it) and downloading the bot screening page instead of the actual pango-1.56.1.tar.gz download. This led to a checksum mismatch and eventually a failed workflow run.

-- Performing post-build validation
Starting submission of cairo[core,fontconfig,freetype,gobject]:x64-windows@1.18.4#1 to 1 binary cache(s) in the background
Elapsed time to handle cairo:x64-windows: 1.1 min
cairo:x64-windows package ABI: 8b09448fd51647d0925b1ec3631d8b0276f97c9f797591ee33ed655b47e4d6d1
Completed submission of pixman:x64-windows@0.44.2 to 1 binary cache(s) in 214 ms
Installing 31/39 pango:x64-windows@1.56.1#2...
Building pango:x64-windows@1.56.1#2...
-- Found Python version '3.12.7 at C:/vcpkg/downloads/tools/python/python-3.12.7-x64-1/python.exe'
-- Using meson: C:/vcpkg/downloads/tools/meson-1.9.0-d1fcc2/meson.py
Downloading https://gitlab.gnome.org//GNOME/pango/-/archive/1.56.1/pango-1.56.1.tar.gz -> GNOME-pango-1.56.1.tar.gz
GNOME-pango-1.56.1.tar.gz.10040.part: error: download from https://gitlab.gnome.org//GNOME/pango/-/archive/1.56.1/pango-1.56.1.tar.gz had an unexpected hash
note: Expected: c980cfed2a4811c32ba473846d7d075e0b949a833089f4cafb436ce7442719307a60eb68956606c315dd6185cb8753df87d4bac140d752eaeaf0b67b17afbd79
note: Actual  : 17263a77457d6474bc56fae5f7972669162c7d25bf0e4b2c368ead4422d534cb5dfae146e2e1b359184c1e64803a380b3d80ff77414ea291c71028d428d3fe5c
CMake Error at scripts/cmake/vcpkg_download_distfile.cmake:136 (message):
  Download failed, halting portfile.
Call Stack (most recent call first):
  scripts/cmake/vcpkg_from_gitlab.cmake:113 (vcpkg_download_distfile)
  ports/pango/portfile.cmake:1 (vcpkg_from_gitlab)
  scripts/ports.cmake:206 (include)


error: building pango:x64-windows failed with: BUILD_FAILED
See https://learn.microsoft.com/vcpkg/troubleshoot/build-failures?WT.mc_id=vcpkg_inproduct_cli for more information.
Elapsed time to handle pango:x64-windows: 406 ms
Please ensure you're using the latest port files with `git pull` and `vcpkg update`.
Then check for known issues at:
  https://github.com/microsoft/vcpkg/issues?q=is%3Aissue+is%3Aopen+in%3Atitle+pango
You can submit a new issue at:
  https://github.com/microsoft/vcpkg/issues/new?title=%5Bpango%5D%20build%20error%20on%20x64-windows&body=Copy%20issue%20body%20from%20collapsed%20section%20%22issue_body.md%22%20in%20the%20ci%20log%20output
issue_body.md

Waiting for 1 remaining binary cache submissions...
Completed submission of cairo[core,fontconfig,freetype,gobject]:x64-windows@1.18.4#1 to 1 binary cache(s) in 792 ms (1/1)
Error: Process completed with exit code 1.

This issue comment has a temporary workaround: microsoft/vcpkg#47984 (comment)

That workaround is what this PR performs.