Add URL argument to bridge-auth-config-update command

[uneet7]

A brief description of the changes in this PR:
PR adds URL argument to bridge-auth-config-update, which is further passed to update-authorizer-config txn type in 0Chain.
Reference Issue: 0chain/0chain#1625
Fixes: #173

Tasks to complete before merging PR:

• Ensure system tests are passing. If not Run them manually to check for any regressions 📋
• Do any new system tests need added to test this change? do any existing system tests need updated? If so create a PR at 0chain/system_test
• Merge your system tests PR to master AFTER merging this PR

Associated PRs (Link as appropriate):

• blobber:
• gosdk: Add URL param to the Authorizer request struct gosdk#563
• system_test:
• zboxcli:
• 0chain: Add delegate wallet ID present check to update authorizer 0chain#1633
• Other: ...

[peterlimg]

lgtm