sagemathgh-41036: Remove tomli
    
tomli is a TOML parser that was needed for Python < 3.11. Since Python
3.11+, tomllib is part of the standard library. tomli-w (TOML writer) is
kept as it's still needed for writing TOML files.

Changes:
- Removed build/pkgs/tomli directory
- Updated package dependencies to remove tomli references
- Remove the unused 3.10 env file

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### ⌛ Dependencies

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URL: sagemath#41036
Reported by: Chenxin Zhong
Reviewer(s): Copilot, Dima Pasechnik, Tobias Diez

Author: Release Manager

build/pkgs/hatchling/dependencies

@@ -1,4 +1,4 @@
- pathspec tomli editables pluggy packaging trove_classifiers | pip $(PYTHON)
+ pathspec editables pluggy packaging trove_classifiers | pip $(PYTHON)
 
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 All lines of this file are ignored except the first.

build/pkgs/importlib_metadata/dependencies

@@ -1,4 +1,4 @@
- zipp typing_extensions | pip tomli $(PYTHON)
+ zipp typing_extensions | pip $(PYTHON)
 
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 All lines of this file are ignored except the first.

build/pkgs/jupyterlab/dependencies

@@ -1,4 +1,4 @@
-async_lru importlib_metadata ipykernel jinja2 jupyter_core jupyter_lsp jupyter_server jupyterlab_server notebook_shim packaging traitlets tornado tomli httpx | $(PYTHON_TOOLCHAIN) $(PYTHON)
+async_lru importlib_metadata ipykernel jinja2 jupyter_core jupyter_lsp jupyter_server jupyterlab_server notebook_shim packaging traitlets tornado httpx | $(PYTHON_TOOLCHAIN) $(PYTHON)
 
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 All lines of this file are ignored except the first.

build/pkgs/meson_python/dependencies

@@ -1,4 +1,4 @@
- meson pyproject_metadata tomli ninja_build patchelf | $(PYTHON_TOOLCHAIN) $(PYTHON)
+ meson pyproject_metadata ninja_build patchelf | $(PYTHON_TOOLCHAIN) $(PYTHON)
 
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 All lines of this file are ignored except the first.

build/pkgs/pytest/dependencies

@@ -1,4 +1,4 @@
-iniconfig packaging pluggy exceptiongroup tomli colorama | pip $(PYTHON)
+iniconfig packaging pluggy exceptiongroup colorama | pip $(PYTHON)
 
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 All lines of this file are ignored except the first.

build/pkgs/python_build/dependencies

@@ -1,4 +1,4 @@
-tomli packaging pyproject_hooks importlib_metadata | pip $(PYTHON)
+packaging pyproject_hooks importlib_metadata | pip $(PYTHON)
 
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 All lines of this file are ignored except the first.

build/pkgs/setuptools_scm/dependencies

@@ -1,4 +1,4 @@
-packaging setuptools tomli typing_extensions | pip $(PYTHON)
+packaging setuptools typing_extensions | pip $(PYTHON)
 
 ----------
 All lines of this file are ignored except the first.