Revert "Delete src/hdmf/build/map.py (#1221)"

This reverts commit 6396a81.

CHANGELOG.md

@@ -4,7 +4,6 @@
 
 ### Deprecations
 - The following classes have been deprecated and removed: Array, AbstractSortedArray, SortedArray, LinSpace, Query, RegionSlicer, ListSlicer, H5RegionSlicer, DataRegion, RegionBuilder. The following methods have been deprecated and removed: fmt_docval_args, call_docval_func, get_container_cls, add_child, set_dataio (now refactored as set_data_io). We have also removed all early development for region references. @mavaylon1, @rly [#1998](https://github.com/hdmf-dev/hdmf/pull/1198), [#1212](https://github.com/hdmf-dev/hdmf/pull/1212)
-- Importing from hdmf.build.map is no longer supported. Import from hdmf.build instead. @rly [#1221](https://github.com/hdmf-dev/hdmf/pull/1221)
 - Python 3.8 has been deprecated. Python 3.9 is the new minimum with support for Python 3.13. @mavaylon1 [#1209](https://github.com/hdmf-dev/hdmf/pull/1209)
 
 ### Enhancements

src/hdmf/build/map.py

@@ -0,0 +1,7 @@
+# this prevents breaking of code that imports these classes directly from map.py
+from .manager import Proxy, BuildManager, TypeSource, TypeMap  # noqa: F401
+from .objectmapper import ObjectMapper  # noqa: F401
+
+import warnings
+warnings.warn('Classes in map.py should be imported from hdmf.build. Importing from hdmf.build.map will be removed '
+              'in HDMF 3.0.', DeprecationWarning, stacklevel=2)