Reorder installation section in README (#12177)

See #12163 (comment)

Author: dhruvmanila

README.md

@@ -116,7 +116,17 @@ For more, see the [documentation](https://docs.astral.sh/ruff/).
 
 ### Installation
 
-Install Ruff with our standalone installers:
+Ruff is available as [`ruff`](https://pypi.org/project/ruff/) on PyPI:
+
+```shell
+# With pip.
+pip install ruff
+
+# With pipx.
+pipx install ruff
+```
+
+Starting with version `0.5.0`, Ruff can be installed with our standalone installers:
 
 ```shell
 # On macOS and Linux.
@@ -130,16 +140,6 @@ curl -LsSf https://astral.sh/ruff/0.5.0/install.sh | sh
 powershell -c "irm https://astral.sh/ruff/0.5.0/install.ps1 | iex"
 ```
 
-Or, from [PyPI](https://pypi.org/project/ruff/):
-
-```shell
-# With pip.
-pip install ruff
-
-# With pipx.
-pipx install ruff
-```
-
 You can also install Ruff via [Homebrew](https://formulae.brew.sh/formula/ruff), [Conda](https://anaconda.org/conda-forge/ruff),
 and with [a variety of other package managers](https://docs.astral.sh/ruff/installation/).