Issue 6159: Extra space on Pravega.io docs (#6161)
Issue 6159: Extra space on Pravega.io docs (#6161)

Removed an extra space in pravega.concepts.md.

Signed-off-by: James Kim <4db2fd001d51b22245d2efb2739d3e4a11f44fc8@gmail.com>

Co-authored-by: Andrei Paduroiu <cc6a3de060c0ab9a541ec1449e35d8fe9d98ae57@users.noreply.github.com>
pravega/pravega,pravega/pravega,pravega/pravega