Update some www.unicode.org URLs to use HTTPS. (GH-18912)

diff --git a/Doc/reference/lexical_analysis.rst b/Doc/reference/lexical_analysis.rst
index c5157ef..7e912aa 100644
--- a/Doc/reference/lexical_analysis.rst
+++ b/Doc/reference/lexical_analysis.rst
@@ -316,7 +316,7 @@
 * *Nd* - decimal numbers
 * *Pc* - connector punctuations
 * *Other_ID_Start* - explicit list of characters in `PropList.txt
-  <http://www.unicode.org/Public/13.0.0/ucd/PropList.txt>`_ to support backwards
+  <https://www.unicode.org/Public/13.0.0/ucd/PropList.txt>`_ to support backwards
   compatibility
 * *Other_ID_Continue* - likewise
 
@@ -934,4 +934,4 @@
 
 .. rubric:: Footnotes
 
-.. [#] http://www.unicode.org/Public/11.0.0/ucd/NameAliases.txt
+.. [#] https://www.unicode.org/Public/11.0.0/ucd/NameAliases.txt