Updated assessment documentation (#873)

Fixes #828

## Changes
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Resolves #..

### Functionality 

- [x] added relevant user documentation
- [ ] added new CLI command
- [ ] modified existing command: `databricks labs ucx ...`
- [ ] added a new workflow
- [ ] modified existing workflow: `...`
- [ ] added a new table
- [ ] modified existing table: `...`

### Tests
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describe any other relevant tests -->

- [ ] manually tested
- [ ] added unit tests
- [ ] added integration tests
- [ ] verified on staging environment (screenshot attached)

Author: dipankarkush-db

docs/assessment.md

@@ -25,9 +25,9 @@ Total number of identified storage locations based on scanning Hive Metastore ta
 # Assessment Widgets
 Assessment widgets query tables in the $inventory database and summarize or detail out findings.
 
-The second row of the report starts with "Readiness", "Assessment Summary", "Table counts by storage" and "Table counts by schema and format"
+The second row of the report starts with "Job Count", "Readiness", "Assessment Summary", "Table counts by storage" and "Table counts by schema and format"
 
-<img width="1512" alt="image" src="https://github.com/databrickslabs/ucx/assets/106815134/41904d8a-c746-4191-be08-2e9e2090935d">
+<img width="1510" alt="image" src="https://github.com/databrickslabs/ucx/assets/106815134/b7ea36a6-165b-4172-933d-b0b049707316">
 
 ## Readiness
 This is a rough summary of the workspace readiness to run Unity Catalog governed workloads. Each line item is the percent of compatible items divided by the total items in the class.