Excavator: Upgrade dependencies (#1284)

versions.lock

@@ -68,7 +68,7 @@ org.glassfish.jersey.ext:jersey-bean-validation:2.25.1 (2 constraints: 98133b60)
 org.glassfish.jersey.media:jersey-media-jaxb:2.25.1 (1 constraints: 3311f9d4)
 org.glassfish.web:javax.el:2.2.4 (1 constraints: 00145665)
 org.hibernate:hibernate-validator:5.4.2.Final (2 constraints: f727b721)
-org.immutables:value:2.7.5 (1 constraints: 10050f36)
+org.immutables:value:2.8.1 (1 constraints: 0d050e36)
 org.javassist:javassist:3.22.0-GA (2 constraints: f61d2fc1)
 org.jboss.logging:jboss-logging:3.3.0.Final (1 constraints: bd10c4b6)
 org.jvnet:animal-sniffer-annotation:1.0 (1 constraints: f20b95eb)

versions.props

@@ -34,7 +34,7 @@ org.assertj:assertj-core = 3.13.2
 org.bouncycastle:bcpkix-jdk15on = 1.64
 org.glassfish.jersey.*:* = 2.25.1
 org.hamcrest:hamcrest-* = 1.3
-org.immutables:value = 2.7.5
+org.immutables:value = 2.8.1
 org.jmock:jmock = 2.12.0
 org.mockito:mockito-core = 3.1.0
 org.slf4j:slf4j-api = 1.7.12