update older-than test to not use hard coded date (#11642) (#11644)

* update older-than test to not use hard coded date

* update docstring to clarify that  compares times to now

* final fix for this bug

Co-authored-by: Daniel Higginbotham <daniel@flyingmachinestudios.com>

src/metabase/util/date_2.clj

@@ -379,8 +379,8 @@
       ZonedDateTime  (t/zoned-date-time))))
 
 (defn older-than?
-  "True if temporal value `t` happened before some period/duration ago. Prefer this over using `t/before?`
-  because it is incredibly fussy about the classes of arguments it is passed.
+  "True if temporal value `t` happened before some period/duration ago, compared to now. Prefer this over using
+  `t/before?` to compare times to now because it is incredibly fussy about the classes of arguments it is passed.
 
     ;; did `t` happen more than 2 months ago?
     (older-than? t (t/months 2))"

test/metabase/util/date_2_test.clj

@@ -381,7 +381,7 @@
 
 (deftest older-than-test
   (let [now (t/instant "2019-12-04T00:45:00Z")]
-    (t/with-clock (t/mock-clock  (t/zone-id "America/Los_Angeles"))
+    (t/with-clock (t/mock-clock now (t/zone-id "America/Los_Angeles"))
       (testing (str "now = " now)
         (doseq [t ((juxt t/instant t/local-date t/local-date-time t/offset-date-time identity)
                    (t/zoned-date-time "2019-11-01T00:00-08:00[US/Pacific]"))]