Bump bouncycastleVersion from 1.77 to 1.78 (#206)

Bumps `bouncycastleVersion` from 1.77 to 1.78.

Updates `org.bouncycastle:bcpg-jdk18on` from 1.77 to 1.78
- [Changelog](https://github.com/bcgit/bc-java/blob/main/docs/releasenotes.html)
- [Commits](https://github.com/bcgit/bc-java/commits)

Updates `org.bouncycastle:bcpkix-jdk18on` from 1.77 to 1.78
- [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:bcpg-jdk18on
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.bouncycastle:bcpkix-jdk18on
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: David Gerber <dg@zapek.com>

build.gradle

@@ -21,7 +21,7 @@ import org.springframework.boot.gradle.plugin.SpringBootPlugin
 
 buildscript {
     ext {
-        bouncycastleVersion = "1.77"
+        bouncycastleVersion = "1.78"
         apacheCommonsCollectionsVersion = "4.4"
         springOpenApiVersion = "2.5.0"
         jsoupVersion = "1.17.2"