Incomplete license metadata in build.gradle

[tapdiego-amzn]

https://github.com/samtools/htsjdk/blob/222d10b4e7be763453e2a0a1886cbec99e15e886/build.gradle#L220 lists MIT as the only license applying to this package. This is inconsistent with the actual licensing as described in the README; additional entries should be included listing the other licenses like LGPL-2.1.