Invalid Format for Partners and Financiers Download Files

**Preconditions**:
The Partners/Financiers section must contain at least one entry with status "Completat".

**Steps of Reproduction**:
1. Navigate to the 'Partners' section
2. Select an entry
3. Click on the kebab menu
4. Click on the "Descarca lista" button

**Expected Result**:
4. An XLS file is downloaded, containing the correct data

**Actual Result**:
4. A file is downloaded, but it is not in the XLS format

**Notes**:
- The issue occurs in both the Partners and Financiers sections
- Also the naming seems to be wrong