Print PASSED at end of tests in preparation for #2897

Author: will-v-pi

test/pico_low_power_test/low_power_test_gpio.c

@@ -140,7 +140,7 @@ int main() {
     busy_wait_ms(SLEEP_TIME_MS);
 #endif
 
-    printf("SUCCESS\n");
+    printf("PASSED\n");
 
     return 0;
 }

test/pico_low_power_test/low_power_test_simple.c

@@ -57,6 +57,6 @@ int main() {
 #endif
     }
 
-    printf("SUCCESS\n");
+    printf("PASSED\n");
     return 0;
 }

test/pico_low_power_test/low_power_test_timers.c

@@ -390,7 +390,7 @@ int main() {
     }
 #endif
 
-    printf("SUCCESS\n");
+    printf("PASSED\n");
 
     return 0;
 }