sagemathgh-38877: Update Pypi.io domain (301 permanent redirect)
    
Which itself redirect pypi.io/(*) to pypi.org/$1,
anything under /package/ redirect directly to files.pythonhosted.org.

Pypi.io is legacy/was temporary so it's a nice things to maybe one day
let the pypa infra team to stop supporting it.
; the pypi.org -> files.pythonhosted.org just avoids an extra redirect,

(Note that one of the changed files is a Python file).

### 📝 Checklist

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- [ ] I have linked a relevant issue or discussion.
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- [ ] I have updated the documentation and checked the documentation
preview.

### ⌛ Dependencies

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URL: sagemath#38877
Reported by: M Bussonnier
Reviewer(s): Kwankyu Lee

Author: Release Manager

build/pkgs/alabaster/checksums.ini

@@ -1,4 +1,4 @@
 tarball=alabaster-VERSION-py3-none-any.whl
 sha1=6c86446396c69236a1542e09771e8d7b8487dcfa
 sha256=b46733c07dce03ae4e150330b975c75737fa60f0a7c591b6c8bf4928a28e2c92
-upstream_url=https://pypi.io/packages/py3/a/alabaster/alabaster-VERSION-py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py3/a/alabaster/alabaster-VERSION-py3-none-any.whl

build/pkgs/anyio/checksums.ini

@@ -1,4 +1,4 @@
 tarball=anyio-VERSION-py3-none-any.whl
 sha1=f5bd548b3a14c9c93622bf04f7c6464e3f44966a
 sha256=c1b2d8f46a8a812513012e1107cb0e68c17159a7a594208005a57dc776e1bdc7
-upstream_url=https://pypi.io/packages/py3/a/anyio/anyio-VERSION-py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py3/a/anyio/anyio-VERSION-py3-none-any.whl

build/pkgs/appdirs/checksums.ini

@@ -1,4 +1,4 @@
 tarball=appdirs-VERSION-py2.py3-none-any.whl
 sha1=fc74022712122436427f8282a47bfa430ec2db56
 sha256=a841dacd6b99318a741b166adb07e19ee71a274450e68237b4650ca1055ab128
-upstream_url=https://pypi.io/packages/py2.py3/a/appdirs/appdirs-VERSION-py2.py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py2.py3/a/appdirs/appdirs-VERSION-py2.py3-none-any.whl

build/pkgs/appnope/checksums.ini

@@ -1,4 +1,4 @@
 tarball=appnope-VERSION.tar.gz
 sha1=4dcd80020b345a184d6da6063a69e25b1d353323
 sha256=1de3860566df9caf38f01f86f65e0e13e379af54f9e4bee1e66b48f2efffd1ee
-upstream_url=https://pypi.io/packages/source/a/appnope/appnope-VERSION.tar.gz
+upstream_url=https://files.pythonhosted.org/packages/source/a/appnope/appnope-VERSION.tar.gz

build/pkgs/argon2_cffi/checksums.ini

@@ -1,4 +1,4 @@
 tarball=argon2-cffi-VERSION.tar.gz
 sha1=c16c1506de0211bdfa23d4d51e780fb4aaff5222
 sha256=d384164d944190a7dd7ef22c6aa3ff197da12962bd04b17f64d4e93d934dba5b
-upstream_url=https://pypi.io/packages/source/a/argon2_cffi/argon2-cffi-VERSION.tar.gz
+upstream_url=https://files.pythonhosted.org/packages/source/a/argon2_cffi/argon2-cffi-VERSION.tar.gz

build/pkgs/argon2_cffi_bindings/checksums.ini

@@ -1,4 +1,4 @@
 tarball=argon2-cffi-bindings-VERSION.tar.gz
 sha1=5a9b8906d9ca73c53c2bf0a2f0a8127fda69e965
 sha256=bb89ceffa6c791807d1305ceb77dbfacc5aa499891d2c55661c6459651fc39e3
-upstream_url=https://pypi.io/packages/source/a/argon2_cffi_bindings/argon2-cffi-bindings-VERSION.tar.gz
+upstream_url=https://files.pythonhosted.org/packages/source/a/argon2_cffi_bindings/argon2-cffi-bindings-VERSION.tar.gz

build/pkgs/arrow/checksums.ini

@@ -1,4 +1,4 @@
 tarball=arrow-VERSION-py3-none-any.whl
 sha1=fd9376ef4788dc2b1c981e6b5beb9048e046c556
 sha256=c728b120ebc00eb84e01882a6f5e7927a53960aa990ce7dd2b10f39005a67f80
-upstream_url=https://pypi.io/packages/py3/a/arrow/arrow-VERSION-py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py3/a/arrow/arrow-VERSION-py3-none-any.whl

build/pkgs/asttokens/checksums.ini

@@ -1,4 +1,4 @@
 tarball=asttokens-VERSION-py2.py3-none-any.whl
 sha1=69a9448cd7fad3007a66f464f9daa35dd28183a6
 sha256=051ed49c3dcae8913ea7cd08e46a606dba30b79993209636c4875bc1d637bc24
-upstream_url=https://pypi.io/packages/py2.py3/a/asttokens/asttokens-VERSION-py2.py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py2.py3/a/asttokens/asttokens-VERSION-py2.py3-none-any.whl

build/pkgs/async_lru/checksums.ini

@@ -1,4 +1,4 @@
 tarball=async_lru-VERSION-py3-none-any.whl
 sha1=99b2ea5d551cbad28e08e45f0d0b00827f9ff73d
 sha256=ff02944ce3c288c5be660c42dbcca0742b32c3b279d6dceda655190240b99224
-upstream_url=https://pypi.io/packages/py3/a/async_lru/async_lru-VERSION-py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py3/a/async_lru/async_lru-VERSION-py3-none-any.whl

build/pkgs/attrs/checksums.ini

@@ -1,4 +1,4 @@
 tarball=attrs-VERSION-py3-none-any.whl
 sha1=563b272af703f8960b76f6637d009fa5fc5864d3
 sha256=99b87a485a5820b23b879f04c2305b44b951b502fd64be915879d77a7e8fc6f1
-upstream_url=https://pypi.io/packages/py3/a/attrs/attrs-VERSION-py3-none-any.whl
+upstream_url=https://files.pythonhosted.org/packages/py3/a/attrs/attrs-VERSION-py3-none-any.whl