Make PR workflows match target-cpu flags in published jars. (#3402)

Author: mbutrovich

.github/workflows/iceberg_spark_test.yml

@@ -77,6 +77,8 @@ jobs:
         # Use CI profile for faster builds (no LTO) and to share cache with pr_build_linux.yml.
         run: |
           cd native && cargo build --profile ci
+        env:
+          RUSTFLAGS: "-Ctarget-cpu=x86-64-v3"
 
       - name: Save Cargo cache
         uses: actions/cache/save@v5

.github/workflows/pr_build_linux.yml

@@ -94,6 +94,8 @@ jobs:
           # CI profile: same overflow behavior as release, but faster compilation
           # (no LTO, parallel codegen)
           cargo build --profile ci
+        env:
+          RUSTFLAGS: "-Ctarget-cpu=x86-64-v3"
 
       - name: Upload native library
         uses: actions/upload-artifact@v6

.github/workflows/pr_build_macos.yml

@@ -94,6 +94,8 @@ jobs:
           # CI profile: same overflow behavior as release, but faster compilation
           # (no LTO, parallel codegen)
           cargo build --profile ci
+        env:
+          RUSTFLAGS: "-Ctarget-cpu=apple-m1"
 
       - name: Upload native library
         uses: actions/upload-artifact@v6

.github/workflows/spark_sql_test.yml

@@ -83,6 +83,8 @@ jobs:
         run: |
           cd native
           cargo build --profile ci
+        env:
+          RUSTFLAGS: "-Ctarget-cpu=x86-64-v3"
 
       - name: Upload native library
         uses: actions/upload-artifact@v6