mautrix-telegram: fix application

* In 0.9 the entrypoint got removed as it's recommended to use
  `python -m`[1]. However, our build layer for python relies on
  that, so I added a patch to re-add this.

* The tests in the upstream sources appear abandoned, so those are
  skipped. Therefore it's also pointless to add `pytest-runner` to the
  `nativeBuildInputs` as it's not used and only blows up the build
  closure.

  A second patch modifies the requirements, so ow `pytest-runner` isn't
  needed anymore.

[1] a565853c5e

pkgs/servers/mautrix-telegram/0001-Re-add-entrypoint.patch

@@ -0,0 +1,29 @@
+From f4a612e1c8501d2a1683003bb121daa6d46155ca Mon Sep 17 00:00:00 2001
+From: Maximilian Bosch <maximilian@mbosch.me>
+Date: Sun, 29 Nov 2020 20:45:16 +0100
+Subject: [PATCH 1/2] Re-add entrypoint
+
+---
+ setup.py | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+diff --git a/setup.py b/setup.py
+index 068c351..95dbf89 100644
+--- a/setup.py
++++ b/setup.py
+@@ -51,6 +51,12 @@ setuptools.setup(
+     extras_require=extras_require,
+     python_requires="~=3.6",
+ 
++    entry_points={
++        'console_scripts': [
++            'mautrix-telegram=mautrix_telegram.__main__:main'
++        ]
++    },
++
+     setup_requires=["pytest-runner"],
+     tests_require=["pytest", "pytest-asyncio", "pytest-mock"],
+ 
+-- 
+2.28.0
+

pkgs/servers/mautrix-telegram/0002-Don-t-depend-on-pytest-runner.patch

@@ -0,0 +1,24 @@
+From eb39954acf73096d65ba1e9575cbeb3d4307d5df Mon Sep 17 00:00:00 2001
+From: Maximilian Bosch <maximilian@mbosch.me>
+Date: Sun, 29 Nov 2020 20:55:17 +0100
+Subject: [PATCH 2/2] Don't depend on pytest-runner
+
+---
+ setup.py | 1 -
+ 1 file changed, 1 deletion(-)
+
+diff --git a/setup.py b/setup.py
+index 95dbf89..89ea2a7 100644
+--- a/setup.py
++++ b/setup.py
+@@ -57,7 +57,6 @@ setuptools.setup(
+         ]
+     },
+ 
+-    setup_requires=["pytest-runner"],
+     tests_require=["pytest", "pytest-asyncio", "pytest-mock"],
+ 
+     classifiers=[
+-- 
+2.28.0
+

pkgs/servers/mautrix-telegram/default.nix

@@ -21,14 +21,11 @@ in buildPythonPackage rec {
     sha256 = "1543ljjl3jg3ayid7ifi4bamqh4gq85pmlbs3m8i7phjbbm7g9dn";
   };
 
+  patches = [ ./0001-Re-add-entrypoint.patch ./0002-Don-t-depend-on-pytest-runner.patch ];
   postPatch = ''
     sed -i -e '/alembic>/d' requirements.txt
   '';
 
-  nativeBuildInputs = [
-    pytestrunner
-  ];
-
   propagatedBuildInputs = [
     Mako
     aiohttp
@@ -58,8 +55,10 @@ in buildPythonPackage rec {
 
   # Tests are broken and throw the following for every test:
   #   TypeError: 'Mock' object is not subscriptable
+  #
+  # The tests were touched the last time in 2019 and upstream CI doesn't even build
+  # those, so it's safe to assume that this part of the software is abandoned.
   doCheck = false;
-
   checkInputs = [
     pytest
     pytest-mock