fix(ingest): fix delta-lake dict iteration bug

[hsheth2]

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable). If a new feature has been added a Usage Guide has been added for the same.
• For any breaking change/potential downtime/deprecation/big changes an entry has been made in Updating DataHub

[github-actions]

Unit Test Results (metadata ingestion)

       8 files         8 suites   1h 15m 56s ⏱️
   643 tests    641 ✔️ 2 💤 0 ❌
1 286 runs  1 281 ✔️ 5 💤 0 ❌

Results for commit 583d0e1.

[github-actions]

Unit Test Results (build & test)

499 tests  ±0   499 ✔️ ±0   9m 20s ⏱️ +38s
115 suites ±0       0 💤 ±0 
115 files   ±0       0 ❌ ±0 

Results for commit 583d0e1. ± Comparison against base commit e9494f5.

[shirshanka]

LGTM