gh-35451: Add modules to modules/index.rst
    
Add vector_numpy_integer_dense and vector_numpy_dense so that hyperlinks
work again.

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This attempts to fix #35444 by adding the correct modules in
`index.rst`. Currently `Vector_numpy_dense` can be accessed through the
index page, but not through the Base class link of
`Vector_double_dense`. Need help resolving this issue.

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@mkoeppe
    
URL: #35451
Reported by: Karan Handa
Reviewer(s): Matthias Köppe

Author: Release Manager

src/doc/en/reference/modules/index.rst

@@ -106,6 +106,8 @@ Vectors
    sage/modules/vector_callable_symbolic_dense
    sage/modules/vector_double_dense
    sage/modules/vector_real_double_dense
+   sage/modules/vector_numpy_dense
+   sage/modules/vector_numpy_integer_dense
    sage/modules/vector_complex_double_dense
    sage/modules/complex_double_vector
    sage/modules/real_double_vector