sagemathgh-39377: Mark test as random to avoid failure

Fix issue pointed out in
sagemath#39153 (comment)

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- [x] The description explains in detail what this PR is about.
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- [x] I have created tests covering the changes.
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URL: sagemath#39377
Reported by: user202729
Reviewer(s):

Author: Release Manager

build/pkgs/configure/checksums.ini

@@ -1,3 +1,3 @@
 tarball=configure-VERSION.tar.gz
-sha1=f9c1bea6113a6a09430ee1f1aca16c75ed427d48
-sha256=c1e0826fb54dd60e78f19e6fcad0b0ef90b33e1771fbbc2165a54c9297a89557
+sha1=01e1e03cf089debd5e1b62ace31b331c91e37b22
+sha256=f47fbefc52031254ccf9aac2c2c609fabb70d976ec61a95f9f93ab980428b93f

build/pkgs/configure/package-version.txt

@@ -1 +1 @@
-5eb37241946a9ef9130ce36eff7e4f135d980eaf
+4f5ae64eb6ce9a9c3eb79f8f14e15af78bcbda88

src/sage/rings/number_field/number_field.py

@@ -8780,40 +8780,10 @@ def subfields(self, degree=0, name=None):
         polynomials are supported (:issue:`252`)::
 
             sage: K.<a> = NumberField(2*x^4 + 6*x^2 + 1/2)
-            sage: sorted(K.subfields(), key=lambda x: x[0].discriminant())
-            [(Number Field in a3 with defining polynomial x^2 + 2,
-              Ring morphism:
-                From: Number Field in a3 with defining polynomial x^2 + 2
-                To:   Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
-                Defn: a3 |--> 2*a^3 + 5*a,
-              None),
-             (Number Field in a2 with defining polynomial x^2 + 4,
-              Ring morphism:
-                From: Number Field in a2 with defining polynomial x^2 + 4
-                To:   Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
-                Defn: a2 |--> 2*a^3 + 7*a,
-              None),
-             (Number Field in a0 with defining polynomial x,
-              Ring morphism:
-                From: Number Field in a0 with defining polynomial x
-                To:   Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
-                Defn: 0 |--> 0,
-              None),
-             (Number Field in a1 with defining polynomial x^2 - 2,
-              Ring morphism:
-                From: Number Field in a1 with defining polynomial x^2 - 2
-                To:   Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
-                Defn: a1 |--> a^2 + 3/2,
-              None),
-             (Number Field in a4 with defining polynomial x^4 + 1,
-              Ring morphism:
-                From: Number Field in a4 with defining polynomial x^4 + 1
-                To:   Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
-                Defn: a4 |--> a^3 + 1/2*a^2 + 5/2*a + 3/4,
-              Ring morphism:
-                From: Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
-                To:   Number Field in a4 with defining polynomial x^4 + 1
-                Defn: a |--> -1/2*a4^3 + a4^2 - 1/2*a4)]
+            sage: K
+            Number Field in a with defining polynomial 2*x^4 + 6*x^2 + 1/2
+            sage: sorted([F.discriminant() for F, _, _ in K.subfields()])
+            [-8, -4, 1, 8, 256]
         """
         return self._subfields_helper(degree=degree, name=name,
                                       both_maps=True, optimize=False)