Increase the timeout for the Win8 GN bot.
Increase the timeout for the Win8 GN bot.

It seems the linking time is sometimes longer than 40 minutes.
Therefore the default timeout is not sufficient.

BUG=

Review URL: https://codereview.chromium.org/1091753002

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@294846 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build