fix(deps): update dependency org.junit:junit-bom to v5.12.1

Author: renovate[bot]

sigstore-java/build.gradle.kts

@@ -45,7 +45,7 @@ dependencies {
     implementation("com.google.oauth-client:google-oauth-client-java6")
 
     testImplementation(project(":sigstore-testkit"))
-    testImplementation(platform("org.junit:junit-bom:5.12.0"))
+    testImplementation(platform("org.junit:junit-bom:5.12.1"))
 
     testImplementation(platform("org.mockito:mockito-bom:5.16.0"))
     testImplementation("org.mockito:mockito-core")

sigstore-testkit/build.gradle.kts

@@ -11,7 +11,7 @@ dependencies {
 
     // This is different from typical "testImplementation" dependencies, because
     // testkit exposes junit5 dependencies in its API (e.g. annotations)
-    api(platform("org.junit:junit-bom:5.12.0"))
+    api(platform("org.junit:junit-bom:5.12.1"))
     api("org.junit.jupiter:junit-jupiter-api")
     api("org.junit.jupiter:junit-jupiter-params")
     implementation("org.junit.jupiter:junit-jupiter")