ruby: update to 2.6.2

ruby: update to 2.6.2

Bug fixes and a security update of the bundled RubyGems:

CVE-2019-8320: Delete directory using symlink when decompressing tar
CVE-2019-8321: Escape sequence injection vulnerability in verbose
CVE-2019-8322: Escape sequence injection vulnerability in gem owner
CVE-2019-8323: Escape sequence injection vulnerability in API response handling
CVE-2019-8324: Installing a malicious gem may lead to arbitrary code execution
CVE-2019-8325: Escape sequence injection vulnerability in errors

Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>