ignore/types: add LLVM to default types

This PR adds llvm to the list of default types, matching files with
extension ll which is used widely for the textual form of LLVM's
Intermediate Representation.

Ref: https://llvm.org/docs/LangRef.html

Closes #3079

crates/ignore/src/default_types.rs

@@ -152,6 +152,7 @@ pub(crate) const DEFAULT_TYPES: &[(&[&str], &[&str])] = &[
     ]),
     (&["lilypond"], &["*.ly", "*.ily"]),
     (&["lisp"], &["*.el", "*.jl", "*.lisp", "*.lsp", "*.sc", "*.scm"]),
+    (&["llvm"], &["*.ll"]),
     (&["lock"], &["*.lock", "package-lock.json"]),
     (&["log"], &["*.log"]),
     (&["lua"], &["*.lua"]),