Update default Guava dependency for Jackson 2.16 from Guava 23.x to 25.x

[cowtowncoder]

(similar to earlier #105)

Although Guava module can work with older versions, there is some value in increasing the default transitive dependency version.

Since there is at least one reported vulnerability against 23, let's move up to 25 (25.1-jre) for Jackson 2.16.