com.google.code.findbugs:jsr305 and the @Nullable annotation

[dbyron0]

Apparently since the transition to build with gradle, com.google.code.findbugs:jsr305 has been on the compile classpath for consumers of testcontainers-java.

From what I can tell, we only need it here for the @Nullable annotations in OkHttpInvocationBuilder.java.

My goal is to get jsr305 off the classpath for consumers to reduce the chance for conflicts (with e.g. com.google.code.findbugs:annotations). One way appears to be switching it to a compileOnly dependency (#913). Another way would be to ditch the @Nullable annotations, though if they're adding value, let's keep 'em.

Got some inspiration from google/guava#1018 (comment).

[dbyron0]

There's also this from guava: google/guava#2960 about them ditching jsr305 one day. I can't say I've totally grasped all the issues, nor what the ideal replacement (if any) for testcontainers would be. Here's a PR to remove @Nullable and the dependency on jsr305 though: #920.

[dbyron0]

And more background here: https://stackoverflow.com/questions/4963300/which-notnull-java-annotation-should-i-use