Add escape sequence to '$' on extention of osf_rdmstatistics when plotting graph by matplotlib

Purpose

Add escape sequence to '$' on extention of osf_rdmstatistics when plotting graph by matplotlib

Does this change require a data migration? If so, what data will we migrate?
What is the level of risk?
- Any permissions code touched?
- Is this an additive or subtractive change, other?
How can QA verify? (Through UI, API, AdminApp or AdminAdminApp?)
- If verifying through API, what's the new version? Please include the endpoints in PR notes or Dev docs.
What features or workflows might this change impact?
How will this impact performance? -->

GRDM-44587