docs: rust: remove unintended blockquote in Quick Start

Remove indentation within the "Hacking" section of the Rust Quick Start
guide, i.e. remove a `<blockquote>` HTML element from the rendered
documentation.
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://github.com/Rust-for-Linux/linux/issues/1103
Fixes: d07479b2 ("docs: add Rust documentation")
Signed-off-by: Jon Mulder <jon.e.mulder@gmail.com>
Link: https://lore.kernel.org/r/20240826-pr-docs-rust-remove-quickstart-blockquote-v1-1-c51317d8d71a@gmail.com
[ Added Fixes tag, reworded slightly and matched title to a previous,
  similar commit. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Documentation/rust/quick-start.rst

@@ -305,7 +305,7 @@ If GDB/Binutils is used and Rust symbols are not getting demangled, the reason
 is the toolchain does not support Rust's new v0 mangling scheme yet.
 There are a few ways out:
 
-  - Install a newer release (GDB >= 10.2, Binutils >= 2.36).
+- Install a newer release (GDB >= 10.2, Binutils >= 2.36).
 
-  - Some versions of GDB (e.g. vanilla GDB 10.1) are able to use
-    the pre-demangled names embedded in the debug info (``CONFIG_DEBUG_INFO``).
+- Some versions of GDB (e.g. vanilla GDB 10.1) are able to use
+  the pre-demangled names embedded in the debug info (``CONFIG_DEBUG_INFO``).