Fix numeric labels

It looks like Elastic APM can store numeric labels after all. It just stores them under `numeric_labels` instead of `labels`.

Author: eerohele

src/clojure_elastic_apm/core.clj

@@ -14,7 +14,10 @@
   (.setLabel span-or-tx (name k) (str v)))
 
 (defn set-label [^Span span-or-tx k v]
-  (.setLabel span-or-tx (name k) (str v)))
+  (cond
+    (number? v) (.setLabel span-or-tx (name k) ^Number v)
+    (boolean? v) (.setLabel span-or-tx (name k) ^boolean v)
+    :else (.setLabel span-or-tx (name k) (str v))))
 
 (defn set-name [^Span span-or-tx name]
   (.setName span-or-tx name))

test/clojure_elastic_apm/core_test.clj

@@ -31,7 +31,7 @@
     (let [tx-details (es-find-first-document (str "(processor.event:transaction%20AND%20transaction.id:" @transaction-id ")"))]
       (is (= "TestTransaction" (get-in tx-details [:transaction :name])))
       (is (= "1" (get-in tx-details [:labels :t1])))
-      (is (= "2" (get-in tx-details [:labels :t2])))
+      (is (= 2 (get-in tx-details [:numeric_labels :t2])))
       (is (= "true" (get-in tx-details [:labels :t3])))
       (is (= "Label 4" (get-in tx-details [:labels :t4])))
       (is (= "test-result" (get-in tx-details [:transaction :result])))