feat(provider)!: remove support for python2 and python3.[3-5]

These versions of python has reached End-of-life. getting rid
of python2 support removes a lot of logic to support two
incompatible python versions in the same version.

src/nvim/eval.lua

@@ -270,8 +270,8 @@ return {
     pum_getpos={},
     pumvisible={},
     py3eval={args=1, base=1},
-    pyeval={args=1, base=1},
-    pyxeval={args=1, base=1},
+    pyeval={args=1, base=1, func="f_py3eval"},
+    pyxeval={args=1, base=1, func="f_py3eval"},
     perleval={args=1, base=1},
     range={args={1, 3}, base=1},
     readdir={args={1, 2}, base=1},