Use try-with-resources to ensure input stream gets closed.

"new File" never returns null; a File object is created even if no file
exists at that path. Using try-with-resources guarantees that the stream
is closed even if an exception is thrown: go/java-practices/closing#try

Test: m TeleService -j && atest TeleServiceTests --start-avd
Bug: 274764512
Change-Id: I68d50bae2dd000170adbf1f7008bcd39a45c4fce
1 file changed