Re-enable 1.63 MSRV builds on Windows

These should pass now that tx-sync has a separate MSRV.

Author: TheBlueMatt

.github/workflows/build.yml

@@ -33,8 +33,6 @@ jobs:
         platform: [ self-hosted, windows-latest, macos-latest ]
         toolchain: [ stable, beta, 1.63.0 ] # 1.63.0 is the MSRV for all crates but `lightning-transaction-sync`.
         exclude:
-          - platform: windows-latest
-            toolchain: 1.63.0
           - platform: windows-latest
             toolchain: beta
           - platform: macos-latest