Merge branch 'release-5.1.0' of https://github.com/Sunbird-Ed/SunbirdEd-portal into release-5.1.0

* 'release-5.1.0' of https://github.com/Sunbird-Ed/SunbirdEd-portal:
  Issue #ED-420 CSS cleanup and themes cleanup & SASS migration
  Issue #SB-31172 fix:Overflow of content in the observation items of observation details page
  Issue #SB-0000 dependency list updated in the readme
  Issue #SB-0000 Update:sl-questionnaire and sl-reports-library angular update to V11
  Issue #SB-0000 Updated:common-consumption to Ng-v11
  Issue #SB-0000 Updated:common-consumption to Ng-v11
  Issue #SB-0000 fix: added updated yarn file
  Issue #SB-0000 Updated:common-consumption to Ng-v11