Filter blocked treebanks from README configs

- Add conditional check to skip blocked treebanks in configs section
- Only treebanks with metadata.blocked == False will appear in dataset card
- Ensures blocked treebanks (e.g., pt_cintil) don't show in HuggingFace UI

This prevents users from seeing configs for treebanks that have no
parquet files due to license restrictions.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

tools/templates/README.tmpl

@@ -48,6 +48,7 @@ tags:
 
 configs:
 {%- for name,metadata in data.items()|sort(attribute='1.dirname') %}
+{%- if not metadata.blocked %}
 - config_name: {{ name }}
   data_files:
   {%- set ns = namespace(dataset_size=0) -%}
@@ -58,6 +59,7 @@ configs:
   {%- if name == 'en_ewt' %}
   default: true
   {%- endif %}
+{%- endif %}
 {%- endfor %}
 ---