GHSA-hfvc-g4fc-pqhx: opentelemetry-go: BSD kenv command not using absolute path enables PATH hijacking

OpenTelemetry's Go SDK has a PATH hijacking vulnerability (PATH hijacking is when an attacker puts a malicious program in a directory that the system searches for commands, so their fake program runs instead of the real one) on BSD and Solaris systems because the `kenv` command is called by its name alone instead of its full path. An attacker with local access can place a malicious `kenv` binary in the system's PATH, which will execute with the application's permissions when OpenTelemetry initializes.