go.mod: bump cockroachdb/errors to v1.13.0

[mvanhorn]

Summary

Bump github.com/cockroachdb/errors from v1.11.3 to v1.13.0 so that downstream projects pairing pebble with a newer getsentry/sentry-go compile cleanly. go mod tidy pulls sentry-go from v0.27.0 to v0.46.0 as a transitive indirect update; no pebble source changes are needed.

Why this matters

As reported in #6092, pebble pins cockroachdb/errors v1.11.3, which transitively requires getsentry/sentry-go v0.27.0. Newer sentry-go releases removed Event.Extra, so any downstream that combines pebble with a newer sentry-go fails to compile:

event.Extra undefined (type *sentry.Event has no field or method Extra)

inside errors@v1.11.3/report/report.go. cockroachdb/errors v1.13.0 migrated Event.Extra to Event.Contexts and moved its sentry-go requirement to v0.46.0, resolving the break. Pebble uses only the stable errors.* wrapping APIs and never imports errors/report or touches sentry.Event, so the migration is internal to the errors package and requires no code changes here. This adoption follows CockroachDB's own upstream direction, since the errors team shipped v1.13.0 specifically for this sentry compatibility fix.

Testing

• go build ./... passes (the previously-failing report path now compiles against sentry-go v0.46.0).
• go mod tidy produces no further diff to go.mod or go.sum.
• go mod verify reports all modules verified.
• go test ./... compiles and passes.

Fixes #6092