fix(parser): error for unexpected token

test/cmdlineTests/recovery_ast_empty_contract/err

@@ -1,4 +1,4 @@
-Error: Expected pragma, import directive or contract/interface/library/struct/enum/constant/function definition.
+Error: Expected pragma, import directive or contract/interface/library/struct/enum/constant/function/error definition.
  --> recovery_ast_empty_contract/input.sol:3:1:
   |
 3 | c

test/libsolidity/syntaxTests/freeFunctions/free_constructor.sol

@@ -1,3 +1,3 @@
 constructor() {}
 // ----
-// ParserError 7858: (0-11): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function definition.
+// ParserError 7858: (0-11): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function/error definition.

test/libsolidity/syntaxTests/freeFunctions/free_fallback.sol

@@ -1,3 +1,3 @@
 fallback(){}
 // ----
-// ParserError 7858: (0-8): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function definition.
+// ParserError 7858: (0-8): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function/error definition.

test/libsolidity/syntaxTests/freeFunctions/free_receive.sol

@@ -1,3 +1,3 @@
 receive() {}
 // ----
-// ParserError 7858: (0-7): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function definition.
+// ParserError 7858: (0-7): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function/error definition.

test/libsolidity/syntaxTests/unexpected.sol

@@ -1,3 +1,3 @@
 unexpected
 // ----
-// ParserError 7858: (0-10): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function definition.
+// ParserError 7858: (0-10): Expected pragma, import directive or contract/interface/library/struct/enum/constant/function/error definition.