Without this change the /{*foobar} and /** path elements were
not correctly enforcing that the first character they encounter
must be a separator. This problem was introduced when adjusting
the generated path element chains for these constructs. Originally
the generated chain included a SeparatorPathElement but in order for
these to match 'nothing' (i.e. /foo matches /foo/{*foobar}) the separator
path element was removed, so the separator enforcement needed moving
into the CaptureTheRestPathElement and WildcardTheRestPathElement.
Issue: SPR-14544