Update docs/index.md

Author: 73rhodes

docs/index.md

@@ -942,11 +942,11 @@ Exits with standard POSIX exit codes instead of the number of failed tests.
 
 Those exit codes are:
 
-* `0`: if all tests passed
-* `1`: if any test failed
-* `128 + <signal>` if given a signal, such as:
-  * 134: `SIGABRT` (`128 + 6`)
-  * 143: `SIGTERM` (`128 + 15`)
+- `0`: if all tests passed
+- `1`: if any test failed
+- `128 + <signal>` if given a signal, such as:
+  - 134: `SIGABRT` (`128 + 6`)
+  - 143: `SIGTERM` (`128 + 15`)
 
 ### `--retries <n>`