gh-38095: `src/sage/algebras/steenrod/all.py`: Use lazy_import, remove deprecated global import
    
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- The change to use `lazy_import` was cherry-picked from #37900
- The global import was deprecated in #32647 (2021)

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### ⌛ Dependencies

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URL: #38095
Reported by: Matthias Köppe
Reviewer(s): Kwankyu Lee

Author: Release Manager

src/sage/algebras/steenrod/all.py

@@ -1,8 +1,7 @@
+# sage_setup: distribution = sagemath-combinat
 """
 The Steenrod algebra
 """
-from sage.algebras.steenrod.steenrod_algebra import SteenrodAlgebra, Sq
 from sage.misc.lazy_import import lazy_import
-lazy_import('sage.algebras.steenrod.steenrod_algebra_bases',
-            'steenrod_algebra_basis',
-            deprecation=(32647, 'removed from namespace'))
+lazy_import('sage.algebras.steenrod.steenrod_algebra', ['SteenrodAlgebra', 'Sq'])
+del lazy_import

src/sage/misc/sageinspect.py

@@ -1280,6 +1280,7 @@ def sage_getfile(obj):
         sage: from sage.misc.sageinspect import sage_getfile
         sage: sage_getfile(sage.rings.rational)
         '...sage/rings/rational.pyx'
+        sage: from sage.algebras.steenrod.steenrod_algebra import Sq                    # needs sage.combinat sage.modules
         sage: sage_getfile(Sq)                                                          # needs sage.combinat sage.modules
         '...sage/algebras/steenrod/steenrod_algebra.py'
         sage: sage_getfile(x)                                                           # needs sage.symbolic
@@ -1358,6 +1359,7 @@ def sage_getfile_relative(obj):
         sage: from sage.misc.sageinspect import sage_getfile_relative
         sage: sage_getfile_relative(sage.rings.rational)
         'sage/rings/rational.pyx'
+        sage: from sage.algebras.steenrod.steenrod_algebra import Sq                    # needs sage.combinat sage.modules
         sage: sage_getfile_relative(Sq)                                                 # needs sage.combinat sage.modules
         'sage/algebras/steenrod/steenrod_algebra.py'
         sage: sage_getfile_relative(x)                                                  # needs sage.symbolic