In change I3fd9fe0317bcd1a59c366e60154b095e8df92327, we deprecated the
'--version' option in favour of a 'VERSION' positional. This was later
removed in change I7795e308497de66329f288b43ecfbf978d67ad75. Update the
docs to reflect this. 'nova-manage api_db sync' were already corrected
in change Ibc49f93b8bd51d9a050acde5ef3dc8aad91321ca and does not need
the same fix, though a minor tweak is included.
Change-Id: I2c0fb04fbc3f6d2074596894782ed3143b0c2338
Signed-off-by: Stephen Finucane <sfinucan@redhat.com>
Closes-Bug: #1840807