gh-80421: Correct definitions of time (#130984)

Based on the Wikipedia article, UTC is better said to be a successor than a renaming of GTC and language agnostic rather than an English-French compromise.

Author: StanFromIreland

Doc/library/time.rst

@@ -52,9 +52,13 @@ An explanation of some terminology and conventions is in order.
    single: Coordinated Universal Time
    single: Greenwich Mean Time
 
-* UTC is Coordinated Universal Time (formerly known as Greenwich Mean Time, or
-  GMT).  The acronym UTC is not a mistake but a compromise between English and
-  French.
+* UTC is `Coordinated Universal Time`_ and superseded `Greenwich Mean Time`_ or
+  GMT as the basis of international timekeeping. The acronym UTC is not a
+  mistake but conforms to an earlier, language-agnostic naming scheme for time
+  standards such as UT0, UT1, and UT2.
+
+.. _Coordinated Universal Time: https://en.wikipedia.org/wiki/Coordinated_Universal_Time
+.. _Greenwich Mean Time: https://en.wikipedia.org/wiki/Greenwich_Mean_Time
 
 .. index:: single: Daylight Saving Time