gh-40048: Fix primes_of_bounded_norm for noninteger entries
    
For noninteger entries, primes_of_bouned_norm used the ceil function to
convert it to an integer. This caused the function to sometimes return
primes of norm bigger than the bound.

Using the floor function instead, fixes the issue.


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preview.
    
URL: #40048
Reported by: Eloi Torrents
Reviewer(s):

Author: Release Manager

src/sage/rings/number_field/number_field.py

@@ -3934,6 +3934,8 @@ def primes_of_bounded_norm(self, B):
              Fractional ideal (3)]
             sage: K.primes_of_bounded_norm(1)
             []
+            sage: K.primes_of_bounded_norm(1.1)
+            []
             sage: x = polygen(QQ, 'x')
             sage: K.<a> = NumberField(x^3 - 2)
             sage: P = K.primes_of_bounded_norm(30)
@@ -3953,7 +3955,7 @@ def primes_of_bounded_norm(self, B):
             B = ZZ(B)
         except (TypeError, AttributeError):
             try:
-                B = ZZ(B.ceil())
+                B = ZZ(B.floor())
             except (TypeError, AttributeError):
                 raise TypeError("%s is not valid bound on prime ideals" % B)
         if B < 2: