[workflow] do not use special android ref for scf (#866)

everything is now merged into main.

Author: hyp

.github/workflows/swift-toolchain.yml

@@ -2069,19 +2069,11 @@ jobs:
           path: ${{ github.workspace }}/SourceCache/swift-corelibs-libdispatch
           show-progress: false
       - uses: actions/checkout@v4
-        if: matrix.os != 'Android'
         with:
           repository: apple/swift-corelibs-foundation
           ref: ${{ inputs.swift_corelibs_foundation_revision }}
           path: ${{ github.workspace }}/SourceCache/swift-corelibs-foundation
           show-progress: false
-      - uses: actions/checkout@v4
-        if: matrix.os == 'Android'
-        with:
-          repository: hyp/swift-corelibs-foundation
-          ref: eng/recore-android-build
-          path: ${{ github.workspace }}/SourceCache/swift-corelibs-foundation
-          show-progress: false
       - uses: actions/checkout@v4
         with:
           repository: apple/swift-foundation