improving the template to avoid generation of code with unsupported types

Author: matteocacciola

pandasai/core/prompts/templates/shared/output_type_template.tmpl

@@ -1,5 +1,5 @@
 {% if not output_type %}
-type (possible values "string", "number", "dataframe", "plot"). Examples: { "type": "string", "value": f"The highest salary is {highest_salary}." } or { "type": "number", "value": 125 } or { "type": "dataframe", "value": pd.DataFrame({...}) } or { "type": "plot", "value": "temp_chart.png" }
+type (possible values "string", "number", "dataframe", "plot"). No other types available. Examples: { "type": "string", "value": f"The highest salary is {highest_salary}." } or { "type": "number", "value": 125 } or { "type": "dataframe", "value": pd.DataFrame({...}) } or { "type": "plot", "value": "temp_chart.png" }
 {% elif output_type == "number" %}
 type (must be "number"), value must int. Example: { "type": "number", "value": 125 }
 {% elif output_type == "string" %}