Fix CI by not building docs Windows on 1.63.0

.. unfortunately the `windows-sys` dependency recently seems to have
broken their doc builds on rustc 1.63.0. As tests and builds still work
without issue, we fix CI by just not building docs on
`windows-latest`/`1.63.0`

.github/workflows/rust.yml

@@ -66,6 +66,7 @@ jobs:
         if: matrix.build-uniffi
         run: cargo build --features uniffi --verbose --color always
       - name: Build documentation on Rust ${{ matrix.toolchain }}
+        if: "matrix.platform != 'windows-latest' || matrix.toolchain != '1.63.0'"
         run: |
           cargo doc --release --verbose --color always
           cargo doc --document-private-items --verbose --color always