chore: disable bootstrap on cross (#4855)

Signed-off-by: Ana Hobden <[email protected]>

Author: Hoverbear

.github/workflows/pr.yml

@@ -140,8 +140,6 @@ jobs:
             ~/.cargo/registry
             ~/.cargo/git
           key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
-      - run: sudo bash scripts/environment/bootstrap-ubuntu-20.04.sh
-      - run: bash scripts/environment/prepare.sh
       - run: echo "::add-matcher::.github/matchers/rust.json"
       - run: make slim-builds
       # Why is this build, not check? Because we need to make sure the linking phase works.