Don't require git user to be configured for testing rust

.github/workflows/nightly-cranelift.yml

@@ -21,10 +21,7 @@ jobs:
         EOF
 
     - name: Prepare dependencies
-      run: |
-        git config --global user.email "user@example.com"
-        git config --global user.name "User"
-        ./y.rs prepare
+      run: ./y.rs prepare
 
     - name: Patch Cranelift
       run: |

.github/workflows/rustc.yml

@@ -24,10 +24,7 @@ jobs:
         EOF
 
     - name: Prepare dependencies
-      run: |
-        git config --global user.email "user@example.com"
-        git config --global user.name "User"
-        ./y.rs prepare
+      run: ./y.rs prepare
 
     - name: Test
       run: ./scripts/test_bootstrap.sh
@@ -51,10 +48,7 @@ jobs:
         EOF
 
     - name: Prepare dependencies
-      run: |
-        git config --global user.email "user@example.com"
-        git config --global user.name "User"
-        ./y.rs prepare
+      run: ./y.rs prepare
 
     - name: Test
       run: ./scripts/test_rustc_tests.sh

scripts/setup_rust_fork.sh

@@ -10,7 +10,7 @@ git fetch
 git checkout -- .
 git checkout "$(rustc -V | cut -d' ' -f3 | tr -d '(')"
 
-git am ../patches/*-sysroot-*.patch
+git -c user.name=Dummy -c user.email=dummy@example.com am ../patches/*-sysroot-*.patch
 
 git apply - <<EOF
 diff --git a/library/alloc/Cargo.toml b/library/alloc/Cargo.toml