Rust 1.68 clippy fixes (#2646)

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This Pull Request addresses the broken `cargo clippy` lints that is currently causing CI to fail.

boa_engine/src/builtins/map/ordered_map.rs

@@ -16,7 +16,7 @@ enum MapKey {
 }
 
 // This ensures that a MapKey::Key(value) hashes to the same as value. The derived PartialEq implementation still holds.
-#[allow(clippy::derive_hash_xor_eq)]
+#[allow(clippy::derived_hash_with_manual_eq)]
 impl Hash for MapKey {
     fn hash<H: Hasher>(&self, state: &mut H) {
         match self {

boa_engine/src/object/internal_methods/integer_indexed.rs

@@ -225,7 +225,6 @@ pub(crate) fn integer_indexed_exotic_own_property_keys(
         // a. For each integer i starting with 0 such that i < O.[[ArrayLength]], in ascending order, do
         // i. Add ! ToString(𝔽(i)) as the last element of keys.
         (0..inner.array_length())
-            .into_iter()
             .map(|index| PropertyKey::Index(index as u32))
             .collect()
     };

boa_engine/src/object/internal_methods/string.rs

@@ -102,7 +102,7 @@ pub(crate) fn string_exotic_own_property_keys(
 
     // 5. For each integer i starting with 0 such that i < len, in ascending order, do
     // a. Add ! ToString(𝔽(i)) as the last element of keys.
-    keys.extend((0..len).into_iter().map(Into::into));
+    keys.extend((0..len).map(Into::into));
 
     // 6. For each own property key P of O such that P is an array index
     // and ! ToIntegerOrInfinity(P) ≥ len, in ascending numeric index order, do

boa_parser/src/lexer/string.rs

@@ -192,7 +192,7 @@ impl StringLiteral {
             0x005C /* \ */ => Some((0x005C /* \ */, None)),
             0x0030 /* 0 */ if cursor
                 .peek()?
-                .filter(|next_byte| (b'0'..=b'9').contains(next_byte))
+                .filter(u8::is_ascii_digit)
                 .is_none() =>
                 Some((0x0000 /* NULL */, None)),
             0x0078 /* x */ => {