Editorial: Remove a few <emu-prodref>s from Annex A

... that I should have removed back in 573e382 (PR tc39#370).

spec.html

@@ -40256,13 +40256,6 @@ <h1>Number Conversions</h1>
     <emu-prodref name=StrNumericLiteral></emu-prodref>
     <emu-prodref name=StrDecimalLiteral></emu-prodref>
     <emu-prodref name=StrUnsignedDecimalLiteral></emu-prodref>
-    <emu-prodref name=DecimalDigits></emu-prodref>
-    <emu-prodref name=DecimalDigit></emu-prodref>
-    <emu-prodref name=ExponentPart></emu-prodref>
-    <emu-prodref name=ExponentIndicator></emu-prodref>
-    <emu-prodref name=SignedInteger></emu-prodref>
-    <emu-prodref name=HexIntegerLiteral></emu-prodref>
-    <emu-prodref name=HexDigit></emu-prodref>
     <p>All grammar symbols not explicitly defined by the |StringNumericLiteral| grammar have the definitions used in the <emu-xref href="#sec-literals-numeric-literals">Lexical Grammar for numeric literals</emu-xref>.</p>
   </emu-annex>