treewide: automatic rewriting of all comment-style type annotations

Performed using https://github.com/ilevkivskyi/com2ann

This has no actual effect on the codebase as type checkers (still)
support both and negligible effect on runtime performance since
__future__ annotations ameliorates that. Technically, the bytecode would
be bigger for non function-local annotations, of which we have many
either way.

So if it doesn't really matter, why do a large-scale refactor? Simple:
because people keep wanting to, but it's getting nickle-and-dimed. If
we're going to do this we might as well do it consistently in one shot,
using tooling that guarantees repeatability and correctness.

Repeat with:

```
com2ann mesonbuild/
```

1 files changed, 1 insertions, 1 deletions

diff --git a/mesonbuild/compilers/detect.py b/mesonbuild/compilers/detect.py
index 210ec4d40..f99724762 100644
--- a/mesonbuild/compilers/detect.py
+++ b/mesonbuild/compilers/detect.py
@@ -969,7 +969,7 @@ def detect_vala_compiler(env: 'Environment', for_machine: MachineChoice) -> Comp
 def detect_rust_compiler(env: 'Environment', for_machine: MachineChoice) -> RustCompiler:
     from . import rust
     from ..linkers import linkers
-    popen_exceptions = {}  # type: T.Dict[str, Exception]
+    popen_exceptions: T.Dict[str, Exception] = {}
     compilers, _, exe_wrap = _get_compilers(env, 'rust', for_machine)
     is_cross = env.is_cross_build(for_machine)
     info = env.machines[for_machine]