trac 33104: after #29310, change refererences to "make doc-clean"

to instead or in addition say "make doc-uninstall".

Author: jhpalmieri

src/doc/en/installation/source.rst

@@ -1020,7 +1020,7 @@ how it is built:
   plots, adding about 4M to the :file:`local/share/doc/sage/` directory.
   In the future, this may grow, of course. Note: after using this, if you
   want to build the documentation and include the pictures, you should
-  run ``make doc-clean``, because the presence, or lack, of pictures
+  run ``make doc-uninstall``, because the presence, or lack, of pictures
   is cached in the documentation output.
   You can benefit from this no-plot feature with other make targets by doing
   ``export SAGE_DOCBUILD_OPTS+=' --no-plot'``
@@ -1036,8 +1036,8 @@ how it is built:
   software, you can use ``make testall``, ``make ptestall``,
   ``make testalllong``, or ``make ptestalllong``.
 
-- ``make doc-clean`` removes several directories which are produced
-  when building the documentation.
+- ``make doc-uninstall`` and ``make doc-clean`` each remove several
+  directories which are produced when building the documentation.
 
 - ``make distclean`` restores the Sage directory to its state before doing any
   building: it is almost equivalent to deleting Sage's entire home directory and

src/sage_docbuild/__init__.py

@@ -1732,7 +1732,7 @@ def excepthook(*exc_info):
             logger.error('''
     Note: incremental documentation builds sometimes cause spurious
     error messages. To be certain that these are real errors, run
-    "make doc-clean" first and try again.''')
+    "make doc-clean doc-uninstall" first and try again.''')
 
     sys.excepthook = excepthook