Add PyTexas 2026 (#276)

Adds PyTexas Conference information

Author: kjaymiller

2026.csv

@@ -1,8 +1,9 @@
 Subject,Start Date,End Date,Location,Country,Venue,Tutorial Deadline,Talk Deadline,Website URL,Proposal URL,Sponsorship URL
 PythonAsia,2026-03-21,2026-03-23,"Malate, Manila",PHL,De La Salle University Manila,,2025-11-30,https://2026.pythonasia.org,https://pretalx.com/python-asia-2026,https://bit.ly/PythonAsia2026-CallForSponsors
 PyCon DE & PyData,2026-04-13,2026-04-17,"Darmstadt, Germany",DEU,datmstadtium,,,https://pycon.de,,
+PyTexas,2026-04-17,2026-04-19,"Austin, Texas United States",USA,Austin Central Library,,2025-12-07,https://www.pytexas.org/2026/,https://pretalx.com/pytexas-2026/,https://www.pytexas.org/2026/sponsors/sponsor-us/
 PyCon US,2026-05-13,2026-05-19,"Long Beach, California, United States of America",USA,,,,https://us.pycon.org,,
 PyCon AU,2026-08-26,2026-08-30,"Brisbane, Australia",AUS,Sofitel Brisbane Central,,,https://2026.pycon.org.au,,
 PyCon PL,2026-08-27,2026-08-30,"Gliwice, Poland",POL,"Education and Congress Centre, Silesian University of Technology",,,https://pl.pycon.org/2026,,
 PyBay,2026-10-03,2026-10-03,"San Francisco, California, United States of America",USA,Mission Bay Conference Center,,2026-07-31,https://pybay.org/,https://pybay.org/speaking/,https://pybay.org/sponsors/sponsor-us/
-PyCon Estonia,2026-10-08,2026-10-09,"Tallinn, Estonia",EST,,,,https://pycon.ee,,
+PyCon Estonia,2026-10-08,2026-10-09,"Tallinn, Estonia",EST,,,,https://pycon.ee,,