Don't process a user pragma if its invalid (#23041)

When running `check`/`suggest` in a file with an invalid user pragma
like
```nim
{.pragma foo: test.}
```
It will continue to try and process it which leads to the compiler
running into a `FieldDefect`
```
fatal.nim(53)            sysFatal
Error: unhandled exception: field 'sons' is not accessible for type 'TNode' using 'kind = nkIdent' [FieldDefect]
```
This makes it instead bail out trying to process the user pragma if its
invalid

1 files changed, 9 insertions, 0 deletions

diff --git a/tests/pragmas/tinvalid_user_pragma.nim b/tests/pragmas/tinvalid_user_pragma.nim
new file mode 100644
index 000000000..3081db842
--- /dev/null
+++ b/tests/pragmas/tinvalid_user_pragma.nim
@@ -0,0 +1,9 @@
+discard """
+cmd: "nim check $file"
+"""
+
+{.pragma test: foo.} #[tt.Error
+^ invalid pragma:  {.pragma, test: foo.} ]#
+
+{.pragma: 1.} #[tt.Error
+^ invalid pragma:  {.pragma: 1.} ]#