gh-30811 introduced explicit support for collections and maps in
ObjectUtils.nullSafeConciseToString() by invoking isEmpty() on a Map or
Collection to determine which concise string representation should be
used. However, this caused a regression in which an exception was
thrown if the Map or Collection was a proxy generated by
AbstractFactoryBean to support <util:set />, <util:list />, and
<util:map /> in XML configuration.
This commit addresses this set of regressions by always returning
"[...]" or "{...}" for a Collection or Map, respectively, disregarding
whether the map is empty or not.
Closes gh-31156
ddcae04ad5