parser: do not fail on comment direct after import (#7071)

vlib/v/checker/tests/comparing_typesymbol_to_a_type_should_not_compile.out

@@ -1,4 +1,4 @@
-vlib/v/checker/comparing_typesymbol_to_a_type_should_not_compile.vv:12:12: error: possible type mismatch of compared values of `==` operation
+vlib/v/checker/tests/comparing_typesymbol_to_a_type_should_not_compile.vv:12:12: error: possible type mismatch of compared values of `==` operation
    10 |     x := ityp == table.string_type
    11 |     // the next line should produce at least a warning, or even an error, without an explicit cast:
    12 |     z := isym == table.string_type

vlib/v/fmt/tests/comment_after_import_expected.vv

@@ -0,0 +1,5 @@
+import semver
+
+// as semver
+fn main() {
+}

vlib/v/fmt/tests/comment_after_import_input.vv

@@ -0,0 +1,4 @@
+import semver// as semver
+
+fn main() {
+}

vlib/v/parser/parser.v

@@ -1624,7 +1624,7 @@ fn (mut p Parser) import_stmt() ast.Import {
 	}
 	pos_t := p.tok.position()
 	if import_pos.line_nr == pos_t.line_nr {
-		if p.tok.kind !in [.lcbr, .eof] {
+		if p.tok.kind !in [.lcbr, .eof, .comment] {
 			p.error_with_pos('cannot import multiple modules at a time', pos_t)
 		}
 	}