fix quickstart release

[qrkourier]

No description provided.

[qrkourier]

@dovholuknf I fixed these issues after your review.

• getZiti() always fails if ZITI_BIN_DIR and ZITI_VERSION_OVERRIDE are both set because _check_env_variable() always fails unless _verify_ziti_version_exists() is run first to set the required values for the override version - solution is to swap the order so _verify_ziti_version_exists() runs first in commit 7d86540
• some release tarballs have a nested directory "ziti" and some don't leading to inconsistent ziti binary path inside the quickstart container image or wherever getZiti() is run - solution is to handle both is a dir and not a dir in commit f26e002

[dovholuknf]

some release tarballs have a nested directory "ziti" and some don't

sounds like the ziti archives need to be fixed to me

[qrkourier]

sounds like the ziti archives need to be fixed to me

I should clarify that old release tarballs had the nested directory, and current release tarballs have only the binary, not nested in a directory. The way I said it before may have sounded like it was inconsistently nested in current releases, which isn't the case.