Update HAPI structures lib version to 6.0.1

[jingtang10]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Description
Update HAPI structures lib version to 6.0.1

Alternative(s) considered
NA

Type
Builds

Screenshots (if applicable)

Checklist

• I have read and acknowledged the Code of conduct.
• I have read the Contributing page.
• I have signed the Google Individual CLA, or I am covered by my company's Corporate CLA.
• I have discussed my proposed solution with code owners in the linked issue(s) and we have agreed upon the general approach.
• I have run ./gradlew spotlessApply and ./gradlew spotlessCheck to check my code follows the style guide of this project.
• I have run ./gradlew check and ./gradlew connectedCheck to test my changes locally.
• I have built and run the demo app(s) to verify my change fixes the issue and/or does not break the demo app(s).

[codecov]

Codecov Report

Merging #1616 (54fddaf) into master (7c964fa) will increase coverage by 35.30%.
The diff coverage is n/a.

❗ Current head 54fddaf differs from pull request most recent head 2cf9866. Consider uploading reports for the commit 2cf9866 to get more accurate results

@@              Coverage Diff              @@
##             master    #1616       +/-   ##
=============================================
+ Coverage          0   35.30%   +35.30%     
- Complexity        0      309      +309     
=============================================
  Files             0      144      +144     
  Lines             0     4830     +4830     
  Branches          0      853      +853     
=============================================
+ Hits              0     1705     +1705     
- Misses            0     2904     +2904     
- Partials          0      221      +221     

Impacted Files	Coverage Δ
...ava/com/google/android/fhir/search/NestedSearch.kt	100.00% <0.00%> (ø)
...src/main/java/com/google/android/fhir/MoreTypes.kt	0.00% <0.00%> (ø)
...temSimpleQuestionAnswerDisplayViewHolderFactory.kt	0.00% <0.00%> (ø)
...oogle/android/fhir/index/entities/QuantityIndex.kt	100.00% <0.00%> (ø)
...m/google/android/fhir/sync/remote/FhirConverter.kt	0.00% <0.00%> (ø)
...roid/fhir/db/impl/DatabaseEncryptionKeyProvider.kt	72.72% <0.00%> (ø)
...r/datacapture/views/QuestionnaireItemHeaderView.kt	95.45% <0.00%> (ø)
...d/fhir/datacapture/fhirpath/ExpressionEvaluator.kt	0.00% <0.00%> (ø)
...java/com/google/android/fhir/search/SearchQuery.kt	100.00% <0.00%> (ø)
...android/fhir/db/impl/entities/NumberIndexEntity.kt	100.00% <0.00%> (ø)
... and 134 more

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[jingtang10]

@vitorpamplona: I tried to use HAPI6 in this separate PR. Would you please take a look at this PR? Thanks!

[vitorpamplona]

If the goal is to keep the engine+sdc at minSDK 24, I would keep HAPI on 5 just to be sure.

The workflow then would require min SDK 26 and replace HAPI 5 with HAPI6 over Java11 when added as a dependency.

[jingtang10]

I tested this on Android API level 24.

Discussed this with @vitorpamplona. While his PR #1603 does reveal issues with usage of HAPI6, it is caused due to the CQL dependencies exercising code paths not previously used in the engine and sdc libs.

For that reason I will go ahead with this PR.

[vitorpamplona]

It should work just fine.

[vorburger]

https://github.com/google/android-fhir/wiki/External-Dependencies now documents this.