Update grammar (#13668)

Fixing a probable oversight in the grammar definition from #12281
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docs/grammar.md

@@ -34,9 +34,9 @@ compileTimeImportTarget ->
 
 importedSymbolsList -> "{" ( NL+ ( importedSymbolsListItem NL+ )* )? "}"
 
-importedSymbolsListItem -> IDENTIFIER(originalSymbolName) importAsClause?
+importedSymbolsListItem -> IDENTIFIER(originalSymbolName) providerAsClause?
 
-wildcardImport -> "*" importAsClause
+wildcardImport -> "*" providerAsClause
 
 compileTimeImportFromClause -> "from" interpString(path)