Log Message:
grafana: Update to 7.5.3

upstream changes:
----------------
7.5.3 (2021-04-07)
Features and enhancements
  o Dashboard: Do not include default datasource when externally exporting \ 
dashboard with row. #32494, @kaydelaney
  o Loki: Remove empty annotations tags. #32359, @conorevans

Bug fixes
  o AdHocVariable: Add default data source to picker. #32470, @hugohaggmark
  o Configuration: Prevent browser hanging / crashing with large number of org \ 
users. #32546, @jackw
  o Elasticsearch: Fix bucket script variable duplication in UI. #32705, @Elfo404
  o Explore: Fix bug where navigating to explore would result in wrong query and \ 
datasource to be shown. #32558, @aocenas
  o FolderPicker: Prevent dropdown menu from disappearing off screen. #32603, @jackw
  o SingleStat: Fix issue with panel links. #32721, @gjulianm
  o Variables: Confirm selection before opening new picker. #32586, @hugohaggmark
  o Variables: Confirm selection before opening new picker. #32503, @hugohaggmark
  o Variables: Fix unsupported data format error for null values. #32480, \ 
@hugohaggmark