update cron-utils to fix CVE sonatype-2020-1438 (opensearch-project#1503)

Signed-off-by: Amardeepsingh Siglani <[email protected]>

Author: amsiglan

core/build.gradle

@@ -13,7 +13,7 @@ dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib:${kotlin_version}"
     api 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.1.1'
     api "org.jetbrains.kotlin:kotlin-stdlib-jdk8:${kotlin_version}"
-    implementation "com.cronutils:cron-utils:9.1.6"
+    implementation "com.cronutils:cron-utils:9.1.7"
     api "org.opensearch.client:opensearch-rest-client:${opensearch_version}"
     implementation('com.google.googlejavaformat:google-java-format:1.10.0')  {
         exclude group: 'com.google.guava'