add env var to disable runtime tracing (#6681)

Recently a PR merged to enable GENAI semantic convention tracing,
however, when using component loading it's not currently possible to
disable the runtime tracing.

---------

Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Co-authored-by: Eric Zhu <ekzhu@users.noreply.github.com>