gh-39488: Fix issue on matrix construction over integer mod ring for large coefficients
    
Fixes #36104.

In previous versions of Python, `int` size was limited and therefore
could be cast to `long`. With Python 3 this limit does not exists and
the code breaks with large integers. We modify the construction of
`Matrix_modn_dense_template`  from Python integers, directly using some
existing cast from Sage.

### 📝 Checklist

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- [x] The title is concise and informative.
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preview.
    
URL: #39488
Reported by: Hugo Passe
Reviewer(s): Vincent Neiger

Author: Release Manager

src/sage/matrix/matrix_modn_dense_template.pxi

@@ -514,6 +514,9 @@ cdef class Matrix_modn_dense_template(Matrix_dense):
             sage: Matrix(Integers(4618990), 2, 2, [-1, int(-2), GF(7)(-3), 1/7])        # needs sage.rings.finite_rings
             [4618989 4618988]
             [      4 2639423]
+
+            sage: Matrix(IntegerModRing(200), [[int(2**128+1), int(2**256+1), int(2**1024+1)]])        # needs sage.rings.finite_rings
+            [ 57 137  17]
         """
         ma = MatrixArgs_init(parent, entries)
         cdef long i, j
@@ -525,10 +528,7 @@ cdef class Matrix_modn_dense_template(Matrix_dense):
             se = <SparseEntry>t
             x = se.entry
             v = self._matrix[se.i]
-            if type(x) is int:
-                tmp = (<long>x) % p
-                v[se.j] = tmp + (tmp<0)*p
-            elif type(x) is IntegerMod_int and (<IntegerMod_int>x)._parent is R:
+            if type(x) is IntegerMod_int and (<IntegerMod_int>x)._parent is R:
                 v[se.j] = <celement>(<IntegerMod_int>x).ivalue
             elif type(x) is Integer:
                 if coerce: