fix(client): use timestamp before issue token request to ensure expiresAt is smaller than token exp

[charIeszhao]

Summary

Calculate the expiresAt by requestedAt + expiresIn, which ensures the calculated result is always smaller than the actual exp property in token claims.

expiresAt = requestedAt + actual request time + expiresIn

Should fix #518

Testing

N/A

Checklist

• [x] .changeset

[linear[bot]]

LOG-6493 ExpireAt and exp in token claims are mismatched

Discussed and decided to add a backward shifted time (60s) to the `expireAt` result.