Update dependency com.squareup.okhttp3:mockwebserver to v5.4.0

Author: renovate[bot]

sigstore-java/build.gradle.kts

@@ -52,7 +52,7 @@ dependencies {
     testImplementation("org.mockito:mockito-junit-jupiter")
 
     testImplementation("no.nav.security:mock-oauth2-server:0.5.10")
-    testImplementation("com.squareup.okhttp3:mockwebserver:5.3.2")
+    testImplementation("com.squareup.okhttp3:mockwebserver:5.4.0")
     testImplementation("net.sourceforge.htmlunit:htmlunit:2.70.0")
 
     testImplementation("io.github.netmikey.logunit:logunit-core:2.0.0")