Use gcc8 to build OutlineProxyController

[Himura2la]

Fixes #1021 refer the issue for description

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[Himura2la]

@googlebot I signed it!

[Himura2la]

Bump. Please, rebuild the binary and check that it matches.

[Himura2la]

The issue  #1021 describes the bug in details. Briefly: if you compile with the latest gcc version, it links to system libraries that does not exist on LTS systems.

[Himura2la]

bump