* Add the Truth dependency
* Port Junit test to Truth in the package `com.google.gson` of the module `gson`
* Replace the `assertThat(e.getMessage()).isEqualTo(...)"` with `assertThat(e).hasMessageThat().isEqualTo(...)`
* Minor fixes
* Remove EOFException special casing of JsonStreamParser.next()
The previous behavior violated the Iterator contract where for
`JsonStreamParser("[")` a call to `hasNext()` would return true,
but `next()` would throw a NoSuchElementException.
* Fix incorrect documented thrown exception type for JsonStreamParser
