bump bouncy castle version from 1.77 to 1.78.1 (#4526)

triggered by dependabot alert 

Fixes PR #4525 (starting at 2.1)
diff --git a/pom.xml b/pom.xml
index fbffd60..463fd29 100644
--- a/pom.xml
+++ b/pom.xml
@@ -147,7 +147,7 @@
     <unitTestMemSize>-Xmx1G</unitTestMemSize>
     <!-- dependency and plugin versions managed with properties -->
     <version.auto-service>1.1.1</version.auto-service>
-    <version.bouncycastle>1.77</version.bouncycastle>
+    <version.bouncycastle>1.78.1</version.bouncycastle>
     <version.curator>5.5.0</version.curator>
     <version.errorprone>2.24.1</version.errorprone>
     <version.hadoop>3.3.6</version.hadoop>