sagemathgh-39364: bump gmpy2 to 2.2.1

    
we now have a new stable version of gmpy2

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preview.

### ⌛ Dependencies

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URL: sagemath#39364
Reported by: Dima Pasechnik
Reviewer(s): Kwankyu Lee

build/pkgs/gmpy2/checksums.ini

@@ -1,4 +1,4 @@
 tarball=gmpy2-VERSION.tar.gz
-sha1=700ef438964acd286d52e973a833cd57ae9a7ad7
-sha256=3b8acc939a40411a8ad5541ed178ff866dd1759e667ee26fe34c9291b6b350c3
+sha1=9dc12136c43f6f5872b0eabc78017745d09f657b
+sha256=e83e07567441b78cb87544910cb3cc4fe94e7da987e93ef7622e76fb96650432
 upstream_url=https://files.pythonhosted.org/packages/source/g/gmpy2/gmpy2-VERSION.tar.gz

build/pkgs/gmpy2/package-version.txt

@@ -1 +1 @@
-2.2.0a1
+2.2.1