Stale bot: staleness after 1 year, close after 2 years

[maelvls]

Slack thread.

I'm annoyed at our stale bot.

We originally turned it on because we (Venafi) used to look at the number of open issues as a vanity metric to tell us that we are doing a good job.... but:

1. We no longer look at this number.
2. These tons of stale messages everywhere are super verbose and annoying.

I suggest issues and PRs become stale after one year, and close them after 2 years. That should reduce the number of stale messages, but still be useful.

Before:

|---------90d----------|----30d----|----30d----|              total = 5 months
active                  stale       rotten     closed

After:

       (1 year)        (6 months)  (6 months)
|--------365d---------|---182d----|---182d----|               total = 2 years
active                 stale       rotten     closed

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Skipping CI for Draft Pull Request.
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[maelvls]

We have had a chat. There are two use-cases I hadn't thought of:

• The stale notifications are used to remind ourselves of some issues we have forgotten about.
• The stale bot is still useful when we don't want to be closing an issue and be seen as obstructive; the bot is a machine, no one can complain.

Not sure whether continuing this PR would make sense.