Fix boot time not returning stat file value

[govrin]

When BootTimeWithContext is called while cache is disabled, the value retrieved from reading the stat file isn't used. Also, I moved the call to time.Now() closer to where the uptime stat is read, to reduce the time between them. This still isn't perfect.

[shirou]

This PR means "the value of useStatFile is not being used" and that seems correct. It only starts being used from the second time onward when caching is enabled. Indeed, now that you mention it... thank you!

The line for currentTime follows the principle of "defining it close to where it is used," but you might be right that it should be moved closer as there are a few steps in between.

So could you fix the golangci-lint ? After that, I will merge.

[govrin]

golangci-lint said something about the file not being gci-ed, but when I ran it locally it didn't show this error. I also tried to run gci with the correct settings and it didn't fix the file. Can you run the CI again?

EDIT: Nevermind, found the problem :)

[shirou]

Great. Thanks a lot!