Fix wrong file name pattern in .gitignore

In .gitignore, there is an entry for spark-*-bin.tar.gz but considering make-distribution.sh, the name pattern should be spark-*-bin-*.tgz.

This change is really small so I don't open issue in JIRA. If it's needed, please let me know.

Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>

Closes #3529 from sarutak/fix-wrong-tgz-pattern and squashes the following commits:

de3c70a [Kousuke Saruta] Fixed wrong file name pattern in .gitignore