#!/bin/bash
url="https://e...content-available-to-author-only...e.com/repository/local/foo-bar/2.15290.0/foo_bar-2.15290.0.tar.gz"
awk 'match($0,/2\.[0-9]+\.0/){print substr($0,RSTART+2,RLENGTH-4)}' <<< "$url"