Fix #1170 Add TimePickerElement to BlockElement.parse

[iress-willygo]

Summary

Fix #1170, TimePickerElement is missing in BlockElement.parse

Category (place an x in each of the [ ])

• slack_sdk.web.WebClient (sync/async) (Web API client)
• slack_sdk.webhook.WebhookClient (sync/async) (Incoming Webhook, response_url sender)
• slack_sdk.socket_mode (Socket Mode client)
• slack_sdk.signature (Request Signature Verifier)
• slack_sdk.oauth (OAuth Flow Utilities)
• slack_sdk.models (UI component builders)
• slack_sdk.scim (SCIM API client)
• slack_sdk.audit_logs (Audit Logs API client)
• slack_sdk.rtm_v2 (RTM client)
• /docs-src (Documents, have you run ./scripts/docs.sh?)
• /docs-src-v2 (Documents, have you run ./scripts/docs-v2.sh?)
• /tutorial (PythOnBoardingBot tutorial)
• tests/integration_tests (Automated tests for this library)

Requirements (place an x in each [ ])

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've run python3 -m venv .venv && source .venv/bin/activate && ./scripts/run_validation.sh after making the changes.

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #1171 (83d8ef2) into main (779cff5) will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main    #1171      +/-   ##
==========================================
- Coverage   86.62%   86.60%   -0.02%     
==========================================
  Files         110      110              
  Lines       10778    10780       +2     
==========================================
  Hits         9336     9336              
- Misses       1442     1444       +2     

Impacted Files	Coverage Δ
slack_sdk/models/blocks/block_elements.py	92.39% <0.00%> (-0.45%)	⬇️

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[seratch]

LGTM. I will add the missing test pattern after merging this.