Bump github.com/cenkalti/backoff/v4 from 4.2.1 to 4.3.0 in /exporters/otlp/otlptrace/otlptracegrpc

Bump github.com/cenkalti/backoff/v4 from 4.2.1 to 4.3.0 in /exporters/otlp/otlptrace/otlptracegrpc #1768