Bump org.bouncycastle:bcprov-jdk18on from 1.76 to 1.78.1

Bumps [org.bouncycastle:bcprov-jdk18on](https://github.com/bcgit/bc-java) from 1.76 to 1.78.1.
- [Changelog](https://github.com/bcgit/bc-java/blob/main/docs/releasenotes.html)
- [Commits](https://github.com/bcgit/bc-java/commits)

---
updated-dependencies:
- dependency-name: org.bouncycastle:bcprov-jdk18on
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

externalized-properties-core/build.gradle.kts

@@ -26,7 +26,7 @@ dependencies {
   testImplementation("com.fasterxml.jackson.dataformat:jackson-dataformat-yaml")
   testImplementation("com.fasterxml.jackson.dataformat:jackson-dataformat-xml")
   // For testing custom JCE providers with DecryptProcessor.JceDecryptor.
-  testImplementation("org.bouncycastle:bcprov-jdk18on:1.76")
+  testImplementation("org.bouncycastle:bcprov-jdk18on:1.78.1")
 }
 
 jmh {