Prohibit Futures.addCallback(Future, Callback) (i. e. using directExecutor() implicitly) using forbidden-apis

[leventov]

This method is deprecated and removed from later versions of Guava for good reasons. Using this method mindlessly causes problems like #8445.

While Druid is stuck with older Guava, it should prohibit the problematic method proactively using forbidden-apis, forcing specifying an executor explicitly, and actually thinking about which executor should be used.

There are currently 19 usages of this method in Druid production code.