In general this template works well for these situations:
SELECT SUM(FT_Long) as FT_Long, SUM(FT_Short) AS FT_Short, SUM(PT_Long) AS PT_Long, SUM(PT_Short) AS PT_Short
FROM
(
SELECT is_full_time, is_short_term,
COUNT(CASE WHEN is_full_time = 1 AND is_short_term = 0 THEN 1 ELSE NULL END) AS FT_Long,
COUNT(CASE WHEN is_full_time = 1 AND is_short_term = 1 THEN 1 ELSE NULL END) AS FT_Short,
COUNT(CASE WHEN is_full_time = 0 AND is_short_term = 0 THEN 1 ELSE NULL END) AS PT_Long,
COUNT(CASE WHEN is_full_time = 0 AND is_short_term = 1 THEN 1 ELSE NULL END) AS PT_Short
FROM job
GROUP by is_full_time, is_short_term
) T
In this case I believe you will get the same results with the following this will depend on what else is in your data that is requiring the group by in your original query
SELECT
SUM(CASE WHEN is_full_time = 1 AND is_short_term = 0 THEN 1 ELSE 0 END) AS FT_Long,
SUM(CASE WHEN is_full_time = 1 AND is_short_term = 1 THEN 1 ELSE 0 END) AS FT_Short,
SUM(CASE WHEN is_full_time = 0 AND is_short_term = 0 THEN 1 ELSE 0 END) AS PT_Long,
SUM(CASE WHEN is_full_time = 0 AND is_short_term = 1 THEN 1 ELSE 0 END) AS PT_Short
FROM job