sagemathgh-37279: Fix some doctest warnings

    
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These are some of the last remaining doctest warnings as of 10.3.beta7,
as seen e.g. in https://github.com/sagemath/sage/pull/37250/files
"Unchanged files with check annotations".

The ones not fixed here will need a solution for:
- sagemath#36099

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- [ ] I have created tests covering the changes.
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### ⌛ Dependencies

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URL: sagemath#37279
Reported by: Matthias Köppe
Reviewer(s): David Coudert

src/sage/geometry/polyhedron/backend_field.py

@@ -90,7 +90,7 @@ def _is_zero(self, x):
             sage: p = Polyhedron([(sqrt(3),sqrt(2))], base_ring=AA)                     # needs sage.rings.number_field sage.symbolic
             sage: p._is_zero(0)                                                         # needs sage.rings.number_field sage.symbolic
             True
-            sage: p._is_zero(1/100000)                                                  # needs sage.rings.number_field
+            sage: p._is_zero(1/100000)                                                  # needs sage.rings.number_field sage.symbolic
             False
         """
         return x == 0

src/sage/rings/finite_rings/integer_mod_ring.py

@@ -617,14 +617,14 @@ def multiplicative_subgroups(self):
 
         EXAMPLES::
 
-            sage: # needs sage.groups
-            sage: Integers(5).multiplicative_subgroups()  # optional - gap_package_polycyclic
+            sage: # optional - gap_package_polycyclic, needs sage.groups
+            sage: Integers(5).multiplicative_subgroups()
             ((2,), (4,), ())
-            sage: Integers(15).multiplicative_subgroups()  # optional - gap_package_polycyclic
+            sage: Integers(15).multiplicative_subgroups()
             ((11, 7), (11, 4), (2,), (11,), (14,), (7,), (4,), ())
-            sage: Integers(2).multiplicative_subgroups()  # optional - gap_package_polycyclic
+            sage: Integers(2).multiplicative_subgroups()
             ((),)
-            sage: len(Integers(341).multiplicative_subgroups())  # optional - gap_package_polycyclic
+            sage: len(Integers(341).multiplicative_subgroups())
             80
 
         TESTS::
@@ -633,7 +633,7 @@ def multiplicative_subgroups(self):
             ((),)
             sage: IntegerModRing(2).multiplicative_subgroups()                          # needs sage.groups
             ((),)
-            sage: IntegerModRing(3).multiplicative_subgroups()                          # needs sage.groups  # optional - gap_package_polycyclic
+            sage: IntegerModRing(3).multiplicative_subgroups()  # optional - gap_package_polycyclic, needs sage.groups
             ((2,), ())
         """
         return tuple(tuple(g.value() for g in H.gens())

src/sage/rings/generic.py

@@ -36,7 +36,7 @@ class ProductTree:
     Similarly, the :meth:`interpolation` method can be used to implement
     the inverse Fast Fourier Transform::
 
-        sage: tree.interpolation(zs).padded_list(len(ys)) == ys
+        sage: tree.interpolation(zs).padded_list(len(ys)) == ys                         # needs sage.rings.finite_rings
         True
 
     This class encodes the tree as *layers*: Layer `0` is just a tuple

src/sage/rings/polynomial/polynomial_rational_flint.pyx

@@ -2127,11 +2127,11 @@ cdef class Polynomial_rational_flint(Polynomial):
 
         ::
 
-            sage: # needs sage.libs.pari
+            sage: # needs sage.groups sage.libs.pari
             sage: f = x^4 - 17*x^3 - 2*x + 1
             sage: G = f.galois_group(pari_group=True); G
             PARI group [24, -1, 5, "S4"] of degree 4
-            sage: PermutationGroup(G)                                                   # needs sage.groups
+            sage: PermutationGroup(G)
             Transitive group number 5 of degree 4
 
         You can use KASH or GAP to compute Galois groups as well.  The advantage is

src/sage/schemes/curves/affine_curve.py

@@ -1801,6 +1801,7 @@ def fundamental_group(self, simplified=True, puiseux=False):
         to the algebraic field::
 
             sage: # needs sage.rings.number_field
+            sage: x = polygen(ZZ)
             sage: a = QQ[x](x^2 + 5).roots(QQbar)[0][0]
             sage: F = NumberField(a.minpoly(), 'a', embedding=a)
             sage: F.inject_variables()