gh-39664: Add some 'not tested' marks to avoid CI failure
    
As in the title. I don't think there's any advantage in running the test
again.

There's only a very small risk of the fixer forget to delete the marker,
but it seems like a nonexistent issue (whichever pull request that fix
it should also remove the `# not tested`)

At least for those that doesn't segmentation fault or hang.

Side note: not sure what's a good solution to this. Maybe we can do
#39470 instead? (but then it
doesn't apply to meson…)

### 📝 Checklist

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- [x] The title is concise and informative.
- [x] 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

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URL: #39664
Reported by: user202729
Reviewer(s):

Author: Release Manager

src/sage/knots/link.py

@@ -3043,7 +3043,7 @@ def homfly_polynomial(self, var1=None, var2=None, normalization='lm'):
             sage: # needs sage.libs.homfly
             sage: L = Link([[[1, -1], [2, -2]], [1, 1]])
             sage: L2 = Link([[1, 4, 2, 3], [2, 4, 1, 3]])
-            sage: L2.homfly_polynomial()
+            sage: L2.homfly_polynomial()  # not tested (:issue:`39544`)
             -L*M^-1 - L^-1*M^-1
             sage: L.homfly_polynomial()
             -L*M^-1 - L^-1*M^-1

src/sage/rings/polynomial/symmetric_ideal.py

@@ -915,7 +915,7 @@ def groebner_basis(self, tailreduce=False, reduced=True, algorithm=None, report=
             ....:      'y_0*z_0 + 2*z_0^2 - 2*z_0 - 1',
             ....:      'y_0^2 + 2*y_0*z_0 - 2*z_0^2 + 2*z_0 - 2',
             ....:      '-y_0^2 - 2*y_0*z_0 - z_0^2 + y_0 - 1'] * X
-            sage: I.groebner_basis()                                                    # needs sage.combinat
+            sage: I.groebner_basis()   # not tested (:issue:`39537`)                    # needs sage.combinat
             [1]
 
             sage: Y.<x,y> = InfinitePolynomialRing(GF(3), order='degrevlex',

src/sage/rings/semirings/tropical_variety.py

@@ -590,7 +590,7 @@ def weight_vectors(self):
             sage: R.<a,b,c,d> = PolynomialRing(T)
             sage: f = R.random_element()
             sage: vec = f.tropical_variety().weight_vectors()[2].values()
-            sage: all(a == vector([0,0,0,0]) for a in [sum(lst) for lst in vec])
+            sage: all(a == vector([0,0,0,0]) for a in [sum(lst) for lst in vec])  # not tested (:issue:`39663`)
             True
         """
         from itertools import combinations

src/sage/schemes/elliptic_curves/ell_point.py

@@ -272,8 +272,8 @@ def _add_(self, other):
             ....:     if xs:
             ....:         pts.append(E(choice(xs), y, z))
             sage: P, Q = pts
-            sage: R = P + Q
-            sage: for d in N.divisors():
+            sage: R = P + Q  # not tested (:issue:`39191`)
+            sage: for d in N.divisors():  # not tested (:issue:`39191`)
             ....:     if d > 1:
             ....:         assert R.change_ring(Zmod(d)) == P.change_ring(Zmod(d)) + Q.change_ring(Zmod(d))
         """