chore(#2787): minimum nvim version 0.9, replace 0.10 deprecated, enable deprecated warnings (#2788)

* refactor(#2787): replace deprecated

* refactor(#2787): enable deprecated checks

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): use inline deprecation disabling

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): replace deprecated

* refactor(#2787): deprecated are now warnings

* refactor(#2787): 0.9 is the minimum supported version

* Revert "refactor(#2787): replace deprecated"

This reverts commit b6b4c32fcb.

* refactor(#2787): suppress deprecated until 0.11

* refactor(#2787): minimum nvim version 0.8 -> 0.9

* refactor(#2787): reset globals

* refactor(#2787): explicitly check for vim.diagnostic.is_enabled function presence

README.md

@@ -28,7 +28,7 @@ Questions and general support: [Discussions](https://github.com/nvim-tree/nvim-t
 
 ## Requirements
 
-[neovim >=0.8.0](https://github.com/neovim/neovim/wiki/Installing-Neovim)
+[neovim >=0.9.0](https://github.com/neovim/neovim/wiki/Installing-Neovim)
 
 [nvim-web-devicons](https://github.com/nvim-tree/nvim-web-devicons) is optional and used to display file icons. It requires a [patched font](https://www.nerdfonts.com/). Your terminal emulator must be configured to use that font, usually "Hack Nerd Font"