Changes HashMap to use aHash instead, giving a performance boost. (#9391)

# Description

see https://github.com/nushell/nushell/issues/9390
using `ahash` instead of the default hasher. this will not affect
compile time as we where already building `ahash`.


# User-Facing Changes
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crates/nu-command/src/viewers/explore.rs

@@ -1,3 +1,4 @@
+use ahash::HashMap;
 use nu_ansi_term::{Color, Style};
 use nu_color_config::{get_color_map, StyleComputer};
 use nu_engine::CallExt;
@@ -11,7 +12,6 @@ use nu_protocol::{
     engine::{Command, EngineState, Stack},
     Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
 };
-use std::collections::HashMap;
 
 /// A `less` like program to render a [Value] as a table.
 #[derive(Clone)]

crates/nu-command/src/viewers/icons.rs

@@ -1,6 +1,6 @@
+use ahash::HashMap;
 use nu_protocol::{ShellError, Span};
 use once_cell::sync::Lazy;
-use std::collections::HashMap;
 use std::path::Path;
 
 // Attribution: Thanks exa. Most of this file is taken from around here
@@ -86,7 +86,7 @@ impl Icons {
 // }
 
 static MAP_BY_NAME: Lazy<HashMap<&'static str, char>> = Lazy::new(|| {
-    HashMap::from([
+    [
         (".Trash", '\u{f1f8}'),             // 
         (".atom", '\u{e764}'),              // 
         (".bashprofile", '\u{e615}'),       // 
@@ -124,7 +124,9 @@ static MAP_BY_NAME: Lazy<HashMap<&'static str, char>> = Lazy::new(|| {
         ("npmignore", '\u{e71e}'),          // 
         ("rubydoc", '\u{e73b}'),            // 
         ("yarn.lock", '\u{e718}'),          // 
-    ])
+    ]
+    .into_iter()
+    .collect()
 });
 
 pub fn icon_for_file(file_path: &Path, span: Span) -> Result<char, ShellError> {