sagemathgh-40575: Fix Drinfeld module frobenius_endomorphism doc

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Fixed an atrocious typo in the description of the
`frobenius_endomorphism` method of the class `DrinfeldModule_finite`.

I followed the notation (the degree of `K` over `\mathbb F_q` is denoted
by `n`) chosen by Xavier @xcaruso in his PR on homsets of Drinfeld
modules (sagemath#40440).

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preview.

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None.

URL: sagemath#40575
Reported by: Antoine Leudière
Reviewer(s):

Author: Release Manager

build/pkgs/configure/checksums.ini

@@ -1,3 +1,3 @@
 tarball=configure-VERSION.tar.gz
-sha1=60867f7d62984944eca465d48e0fb31abde2841e
-sha256=4ec557fb0516afe91e097986429d4e1c65e035cee5b9a8f21b17d3c1db9212d7
+sha1=f700d099c8b4674e7d27e1cd380d198c93275123
+sha256=5672b09596de90b6302fe528b5fdd55253eb3e04d1f37a2fac589df1967e5fe7

build/pkgs/configure/package-version.txt

@@ -1 +1 @@
-858268b40010e5ed6da13488ad0f52cda4d1f70e
+fe2673aff0580a12db44c31abf81fc7c189286d8

src/sage/rings/function_field/drinfeld_modules/finite_drinfeld_module.py

@@ -230,12 +230,12 @@ def companion(order):
 
     def frobenius_endomorphism(self):
         r"""
-        Return the Frobenius endomorphism of the Drinfeld module as a
-        morphism object.
+        Return the Frobenius endomorphism of the Drinfeld module.
+
+        The *Frobenius endomorphism* is defined by the Ore polynomial
+        `tau^n`, where `n` is the degree of the base field `K` over
+        `\mathbb F_q`.
 
-        Let `q` be the order of the base field of the function ring. The
-        *Frobenius endomorphism* is defined as the endomorphism whose
-        defining Ore polynomial is `t^q`.
 
         EXAMPLES::