Update project name GetFEM++ -> GetFEM (#11977)

Author: tkoyama010

EXAMPLES.rst

@@ -66,7 +66,7 @@ Documentation using the classic theme
 * `EZ-Draw <https://pageperso.lis-lab.fr/~edouard.thiel/ez-draw/doc/en/html/ez-manual.html>`__ (customized)
 * `Generic Mapping Tools (GMT) <https://gmt.soest.hawaii.edu/doc/latest/>`__ (customized)
 * `Genomedata <https://noble.gs.washington.edu/proj/genomedata/doc/1.3.3/>`__
-* `GetFEM++ <https://getfem.org/>`__ (customized)
+* `GetFEM <https://getfem.org/>`__ (customized)
 * `Glasgow Haskell Compiler <https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/>`__ (customized)
 * `Grok <https://web.archive.org/web/20230708190705/http://grok.zope.org/doc/current/>`__ (customized)
 * `GROMACS <https://manual.gromacs.org/documentation/>`__