feat: add txt_record filter to format TXT records (#721)

##### SUMMARY

The format of TXT records must consist of one or many quoted strings of
255 characters.

Use this function to format TXT record that must match the format
required by the API:

```yml
- name: Create a SPF record
  hetzner.hcloud.zone_rrset:
    zone: example.com
    name: "@"
    type: "TXT"
    records:
      - value: "{{ 'v=spf1 include:_spf.example.net ~all' | hetzner.hcloud.text_record }}"
    state: present
```

##### ISSUE TYPE

- Feature Pull Request


##### COMPONENT NAME

zone_rrset

plugins/filter/all.py

@@ -47,6 +47,25 @@ def load_balancer_status(load_balancer: dict, *args, **kwargs) -> Literal["unkno
         raise AnsibleFilterError(f"load_balancer_status - {to_native(exc)}", orig_exc=exc) from exc
 
 
+# pylint: disable=unused-argument
+def txt_record(record: str, *args, **kwargs) -> str:
+    """
+    Return the status of a Load Balancer based on its targets.
+    """
+    try:
+        record = record.replace('"', '\\"')
+
+        parts = []
+        for start in range(0, len(record), 255):
+            end = min(start + 255, len(record))
+            parts.append('"' + record[start:end] + '"')
+        record = " ".join(parts)
+
+        return record
+    except Exception as exc:
+        raise AnsibleFilterError(f"txt_record - {to_native(exc)}", orig_exc=exc) from exc
+
+
 class FilterModule:
     """
     Hetzner Cloud filters.
@@ -55,4 +74,5 @@ class FilterModule:
     def filters(self):
         return {
             "load_balancer_status": load_balancer_status,
+            "txt_record": txt_record,
         }