sagemathgh-38567: Documentation: Remove traces of Trac

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Removing the notice on the transition to GitHub from the Developer
Guide, as well as two small traces in other documentation.

### 📝 Checklist

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- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation and checked the documentation
preview.

### ⌛ Dependencies

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URL: sagemath#38567
Reported by: Matthias Köppe
Reviewer(s): Kwankyu Lee

build/pkgs/configure/checksums.ini

@@ -1,3 +1,3 @@
 tarball=configure-VERSION.tar.gz
-sha1=e162e0f52da5eca0c01ddf4831edcea1acd72033
-sha256=2033521228294e134368d69457d6e582706e84ff10bf3d6d0a57a2a4afad0a8b
+sha1=61bb2523f804345a0862c720a6f0a632c23a950d
+sha256=08421205b72bb0f1ccd75c45b1fd14564c29a77fa412f3f2a46d1e77373dbb6b

build/pkgs/configure/package-version.txt

@@ -1 +1 @@
-b178c10a7401b381b8ed2daab5aaf026436452c9
+2d86061ac581f64727e0fcca6cfd40d2160b282d

docker/README.md

@@ -49,7 +49,7 @@ Have a look at `.gitlab-ci.yml` if you want to setup GitLab CI for your own fork
 
 # Report bugs and issues
 
-Please tell us of any bugs or omissions at our [Issue Tracker](https://trac.sagemath.org) or contact us through the [sage-support](https://groups.google.com/forum/#!forum/sage-support) or the [sage-devel](https://groups.google.com/forum/#!forum/sage-devel) mailing lists.
+Please tell us of any bugs or omissions at our [Issue Tracker](https://github.com/sagemath/sage/issues) or contact us through the [sage-support](https://groups.google.com/forum/#!forum/sage-support) or the [sage-devel](https://groups.google.com/forum/#!forum/sage-devel) mailing lists.
 
 # License
 

src/doc/en/developer/index.rst

@@ -4,14 +4,6 @@
 Welcome to Sage Developer Guide
 ===============================
 
-.. NOTE::
-
-    Sage development moved to `GitHub <https://github.com/sagemath>`_ in
-    February 2023, from `the Sage Trac server <https://trac.sagemath.org>`_,
-    which had been the center of Sage development for a long time. After the
-    transition, this guide was updated accordingly. However, the legacy is
-    still with us in many aspects of the current Sage development.
-
 Everybody who uses Sage is encouraged to contribute something back to Sage at
 some point. You could:
 

src/doc/it/faq/faq-contribute.rst

@@ -158,8 +158,8 @@ Consulta anche la Guida dello Sviluppo Sage, specialmente il capitolo
 `Convenzioni per scrivere codice sorgente in Sage <https://doc.sagemath.org/html/en/developer/#sage-coding-details>`_.
 
 
-Ho inviato al server trac una correzione molte settimane fa. Perché la state ignorando?
-"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+Ho inviato al GitHub Sage repo una correzione molte settimane fa. Perché la state ignorando?
+""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
 
 Non stiamo cercando di ignorare la tua correzione.
 Le persone che lavorano su Sage lo fanno nel loro tempo libero.