Update Bouncy Castle to 1.59

- pick up CVE fixes, etc.
  https://www.bouncycastle.org/latest_releases.html

Change-Id: Iced880a43cd5250a4fa5af32528f43ed29a5ed6f
diff --git a/lib/deps.json b/lib/deps.json
index d62dbf2..27db13d 100644
--- a/lib/deps.json
+++ b/lib/deps.json
@@ -276,8 +276,8 @@
     "google-code-findbugs-3.0.0": "mvn:com.google.code.findbugs:jsr305:3.0.0",
     "google-errorprone-2.0.19": "mvn:com.google.errorprone:error_prone_annotations:2.0.19",
     "google-instrumentation-0.3.0": "mvn:com.google.instrumentation:instrumentation-api:0.3.0",
-    "bcpkix-jdk15on": "mvn:org.bouncycastle:bcpkix-jdk15on:1.58",
-    "bcprov-jdk15on": "mvn:org.bouncycastle:bcprov-jdk15on:1.58",
+    "bcpkix-jdk15on": "mvn:org.bouncycastle:bcpkix-jdk15on:1.59",
+    "bcprov-jdk15on": "mvn:org.bouncycastle:bcprov-jdk15on:1.59",
     "hamcrest-optional": "mvn:com.spotify:hamcrest-optional:1.1.0",
     "swagger-annotations": "mvn:io.swagger:swagger-annotations:1.5.16",
     "kafka-clients": "mvn:org.apache.servicemix.bundles:org.apache.servicemix.bundles.kafka-clients:0.8.2.2_1",