Increase job count for heap tests

tools/ci/config/target-test.yml

@@ -502,7 +502,7 @@ UT_034:
 
 UT_035:
   extends: .unit_test_s2_template
-  parallel: 27
+  parallel: 28
   tags:
     - ESP32S2_IDF
     - UT_T1_1