try fix test_importlib hang in codecoverage collection

Author: coolreader18

.github/workflows/cron-ci.yaml

@@ -37,14 +37,17 @@ jobs:
         working-directory: ./extra_tests
         continue-on-error: true
       - name: run cpython tests
-        run: LLVM_PROFILE_FILE="$PWD/regrtest.profraw" target/release/rustpython -m test -v
+        run: LLVM_PROFILE_FILE="$PWD/regrtest-%p.profraw" target/release/rustpython -m test -v -x test_importlib
+        continue-on-error: true
+      - name: run test_importlib, separately
+        run: LLVM_PROFILE_FILE="$PWD/regrtest-%p.profraw" target/release/rustpython -m test -v -x test_importlib
         continue-on-error: true
       - name: prepare code coverage data
         run: |
           rusttool() {
             local tool=$1; shift; "$(rustc --print target-libdir)/../bin/llvm-$tool" "$@"
           }
-          rusttool profdata merge extra_tests/snippet-*.profraw regrtest.profraw --output codecov.profdata
+          rusttool profdata merge extra_tests/snippet-*.profraw regrtest-*.profraw --output codecov.profdata
           rusttool cov export --instr-profile codecov.profdata target/release/rustpython --format lcov > codecov_tmp.lcov
           lcov -e codecov_tmp.lcov "$PWD"/'*' -o codecov_tmp2.lcov
           lcov -r codecov_tmp2.lcov "$PWD"/target/'*' -o codecov.lcov  # remove LALRPOP-generated parser