LibJS: Disallow U+2212 MINUS SIGN in time zone offset strings

This is a normative change in the ECMA-262 spec. See:
e7f1e5d

Userland/Libraries/LibJS/Runtime/Date.cpp

@@ -608,21 +608,21 @@ bool is_time_zone_offset_string(StringView offset_string)
 // 21.4.1.33.2 ParseTimeZoneOffsetString ( offsetString ), https://tc39.es/ecma262/#sec-parsetimezoneoffsetstring
 double parse_time_zone_offset_string(StringView offset_string)
 {
-    // 1. Let parseResult be ParseText(StringToCodePoints(offsetString), UTCOffset).
+    // 1. Let parseResult be ParseText(offsetString, UTCOffset).
     auto parse_result = Temporal::parse_iso8601(Temporal::Production::TimeZoneNumericUTCOffset, offset_string);
 
     // 2. Assert: parseResult is not a List of errors.
     VERIFY(parse_result.has_value());
 
-    // 3. Assert: parseResult contains a TemporalSign Parse Node.
+    // 3. Assert: parseResult contains a ASCIISign Parse Node.
     VERIFY(parse_result->time_zone_utc_offset_sign.has_value());
 
-    // 4. Let parsedSign be the source text matched by the TemporalSign Parse Node contained within parseResult.
+    // 4. Let parsedSign be the source text matched by the ASCIISign Parse Node contained within parseResult.
     auto parsed_sign = *parse_result->time_zone_utc_offset_sign;
     i8 sign { 0 };
 
-    // 5. If parsedSign is the single code point U+002D (HYPHEN-MINUS) or U+2212 (MINUS SIGN), then
+    // 5. If parsedSign is the single code point U+002D (HYPHEN-MINUS), then
-    if (parsed_sign.is_one_of("-"sv, "\xE2\x88\x92"sv)) {
+    if (parsed_sign == "-"sv) {
         // a. Let sign be -1.
         sign = -1;
     }

Userland/Libraries/LibJS/Runtime/Temporal/ISO8601.cpp

@@ -64,11 +64,8 @@ bool ISO8601Parser::parse_sign()
 {
     // Sign :
     //     ASCIISign
-    //     U+2212
     StateTransaction transaction { *this };
-    auto success = parse_ascii_sign()
+    if (!parse_ascii_sign())
-        || m_state.lexer.consume_specific("\xE2\x88\x92"sv);
-    if (!success)
         return false;
     m_state.parse_result.sign = transaction.parsed_string_view();
     transaction.commit();

Userland/Libraries/LibJS/Tests/builtins/Temporal/TimeZone/TimeZone.js

@@ -16,9 +16,14 @@ describe("errors", () => {
         expect(() => {
             new Temporal.TimeZone("0123456");
         }).toThrowWithMessage(RangeError, "Invalid time zone name '0123456'");
+
         expect(() => {
             new Temporal.TimeZone("23:59:59.9999999999");
         }).toThrowWithMessage(RangeError, "Invalid time zone name '23:59:59.9999999999'");
+
+        expect(() => {
+            new Temporal.TimeZone("\u221201");
+        }).toThrowWithMessage(RangeError, "Invalid time zone name '\u221201'");
     });
 });
 
@@ -58,7 +63,6 @@ describe("normal behavior", () => {
         const signs = [
             ["+", "+"],
             ["-", "-"],
-            ["\u2212", "-"],
         ];
         const values = [
             ["01", "01:00"],