gh-41116: bump cysignals to 1.12.6, cypari to 2.2.4
    
This provides support for Python 3.14, and drops Python 3.11


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### ⌛ Dependencies

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- #40936: needed for CI to pass
    
URL: #41116
Reported by: Dima Pasechnik
Reviewer(s): Chenxin Zhong

Author: Release Manager

build/pkgs/cypari/checksums.ini

@@ -1,4 +1,4 @@
 tarball=cypari2-VERSION.tar.gz
-sha1=5d91408a6e28e43d429667554d2696cfbd58c35b
-sha256=13a338735ea221c1068f8fc415561bf777d8c68725702bc749547264fd091720
+sha1=db84720d85a31e8469d3ec209373654ef64e1954
+sha256=f9f0e994a9a0b064619320411e1d9c303158847e055b58082efdade5ac97f613
 upstream_url=https://files.pythonhosted.org/packages/source/c/cypari2/cypari2-VERSION.tar.gz

build/pkgs/cypari/package-version.txt

@@ -1 +1 @@
-2.2.2
+2.2.4

build/pkgs/cysignals/checksums.ini

@@ -1,4 +1,4 @@
 tarball=cysignals-VERSION.tar.gz
-sha1=d3f23d9d82aab06939996f8cbc881a1c529cab98
-sha256=4aefa3b35eb036cb40b2b948df84725976b987895338204f64550e2d63891f5f
+sha1=b2d50718c6da0d92702fec99291d4bb3b43aed0d
+sha256=3ef3a37bdb244821b85475a08e2762ca1019570b369e321504995fa9a54675ce
 upstream_url=https://files.pythonhosted.org/packages/source/c/cysignals/cysignals-VERSION.tar.gz

build/pkgs/cysignals/package-version.txt

@@ -1 +1 @@
-1.12.4
+1.12.6