[SYNPY-1283] Adds Missing Trailing Space (Broken Link Fix)

[BWMac]

This PR follows-on from #989 to add a trailing space to the URL that I replaced earlier.

[pep8speaks]

Hello @BWMac! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file synapseclient/__main__.py:

Line 940:89: E501 line too long (143 > 88 characters)