Fix command timing on Bash 5.1+ with LP not last

If __lp_set_prompt() was not the last in the PROMPT_COMMAND array, the
command that ran right after it would get marked as the start of the
command, and the timing would begin then. Obviously, timing the time
spent typing a command is not very useful.

The fix is to set the AT_PROMPT when the very last PROMPT_COMMAND is
ran. This can be checked by looking at the last item in the array.

Unfortunately, this will not always work. It is possible to set an entry
in the PROMPT_COMMAND array to a compound command, like:
`my first command; my second command`

In this case, Bash will run the DEBUG trap twice, once with BASH_COMMAND
set to "my first command", and the second to "my second command". This
will fail our check, meaning the start time is never set.

The fix is to check for a BASH_COMMAND with the same ending as the last
PROMPT_COMMAND. It is possible this might match early in very special
circumstances, but even in that case, the last command will reset
everything without problems.

liquidprompt

@@ -4859,13 +4859,19 @@ __lp_before_command() {
         fi
     fi
 
-    # If this is when the prompt is being drawn, the command is done,
+    # If this is the last thing before prompt is being drawn, the command is done,
     # so mark the next trap. Note these two events could be at the same
     # time, so no elif is used.
-    if [[ "$BASH_COMMAND" == __lp_set_prompt ]]; then
-        _LP_AT_PROMPT=1
+    local command
+    if (( ${BASH_VERSINFO[0]:-0} > 5 || ( ${BASH_VERSINFO[0]:-0} == 5 && ${BASH_VERSINFO[1]:-0} >= 1 ) )); then
+        command=${PROMPT_COMMAND[-1]}
+    else
+        command=$PROMPT_COMMAND
     fi
 
+    if [[ "$command" == *"$BASH_COMMAND" ]]; then
+        _LP_AT_PROMPT=1
+    fi
 }
 
 prompt_tag() {