sagemathgh-38095: src/sage/algebras/steenrod/all.py: Use lazy_impor…

…t, remove deprecated global import

    
<!-- ^ Please provide a concise and informative title. -->
<!-- ^ Don't put issue numbers in the title, do this in the PR
description below. -->
<!-- ^ For example, instead of "Fixes sagemath#12345" use "Introduce new method
to calculate 1 + 2". -->
<!-- v Describe your changes below in detail. -->
<!-- v Why is this change required? What problem does it solve? -->
<!-- v If this PR resolves an open issue, please link to it here. For
example, "Fixes sagemath#12345". -->

- The change to use `lazy_import` was cherry-picked from sagemath#37900
- The global import was deprecated in sagemath#32647 (2021)

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. -->

- [x] The title is concise and informative.
- [ ] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation and checked the documentation
preview.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on. For example,
-->
<!-- - sagemath#12345: short description why this is a dependency -->
<!-- - sagemath#34567: ... -->
    
URL: sagemath#38095
Reported by: Matthias Köppe
Reviewer(s): Kwankyu Lee

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