Enabling SystemCheck crash tests for postsubmit

Removing @Ignore annotation so that SystemCheck tests will run in
postsubmit for stability investigation.  Blocking of the class in
presubmit is handled with .gcl configs

Bug: 126760989

Test: yes with am instrument run of the .apk
Change-Id: I6999376ada887f8a25ee5abe42b08cd58931eb3d
diff --git a/tests/functional/devicehealthchecks/src/com/android/devicehealthchecks/SystemCheck.java b/tests/functional/devicehealthchecks/src/com/android/devicehealthchecks/SystemCheck.java
index ac15cd7..5637216 100644
--- a/tests/functional/devicehealthchecks/src/com/android/devicehealthchecks/SystemCheck.java
+++ b/tests/functional/devicehealthchecks/src/com/android/devicehealthchecks/SystemCheck.java
@@ -34,25 +34,21 @@
 @RunWith(AndroidJUnit4.class)
 public class SystemCheck extends CrashCheckBase {
 
-    @Ignore("b/126760989")
     @Test
     public void system_server_crash() {
         checkCrash("system_server_crash");
     }
 
-    @Ignore("b/126760989")
     @Test
     public void system_server_native_crash() {
         checkCrash("system_server_native_crash");
     }
 
-    @Ignore("b/126760989")
     @Test
     public void system_server_anr() {
         checkCrash("system_server_anr");
     }
 
-    @Ignore("b/126760989")
     @Test
     public void system_tombstone() {
         checkCrash("SYSTEM_TOMBSTONE");