Add xargs to jq image for big bang package testing

Big Bang uses this image to test fluent-bit. Removal of xargs broke our script that checks valid api version in the image. Install xargs to the image.

Big Bang test script https://repo1.dso.mil/big-bang/product/packages/fluentbit/-/blob/main/chart/tests/scripts/api-check.sh?ref_type=heads#L17