Fixes three issues:
1. Retrieving the latest evaluation index was not properly selecting the
greatest index. This would undermine checks we had to reduce the number
of evaluations created when the latest eval index was greater than any
alloc change
2. Fix an issue where the blocking query code was using the incorrect
index such that the index was higher than necassary.
3. Special case handling of blocked evaluation since the create/snapshot
index is no particularly useful since they can be reblocked.
This PR changes behavior of the scheduler such that a task group with a
deployment that is failed or paused will not cause the scheduler to skip
migrations.
The reason for this change is that it causes a bad UX when draining
nodes with allocations that are part of a failed/paused deployment.
These operations should not be coupled in any way and this remedies
that.
Prior behavior was still correct, but required either jobs to
transistion to a healthy state or for the node to hit its drain
deadline.
Previously we did a validation pass over CA PEM files before calling
Go's CertPool.AppendCertsFromPEM to provide more detailed error messages
than the stdlib provides.
Unfortunately our validation was overly strict and rejected valid CA
files. This is actually the reason the stdlib PEM parser doesn't return
meaningful errors: PEM files are extremely permissive and it's difficult
to tell the difference between invalid data and valid metadata.
This PR removes our custom validation as it would reject valid data and
the extra error messages were not useful in diagnosing the error
encountered.
Not setting the host name led the Go HTTP client to expect a certificate
with a DNS-resolvable name. Since Nomad uses `${role}.${region}.nomad`
names ephemeral dir migrations were broken when TLS was enabled.
Added an e2e test to ensure this doesn't break again as it's very
difficult to test and the TLS configuration is very easy to get wrong.
