target_link_libraries: Restore LINK_ONLY for multiple static lib dependencies
Since !6989 (merged) we accumulate consecutive non-keyword arguments to recover an unquoted generator expression as a single entry. When given multiple consecutive non-genex library names, the grouping breaks our logic that expects each entry is either a raw target name or a genex. Revise the logic to only accumulate multiple arguments when they end inside a partial genex.
This bug caused target_link_libraries
to stop wrapping static library
private dependencies in $<LINK_ONLY:...>
for INTERFACE_LINK_LIBRARIES
when multiple consecutive library names are given. Add a test case
covering that behavior.
Fixes: #23302 (closed)
Backport: release