fix(libzkp): set StorageTrace optional in ChunkProof

[silathdiir]

Purpose or design rationale of this PR

StorageTrace was used to generate padding chunks before, but we use different method to generate for now.
Set it optional to be compatible with old DB records.

Related zkevm-circuits PR scroll-tech/zkevm-circuits#964 (merged)

PR title

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• build: Changes that affect the build system or external dependencies (example scopes: yarn, eslint, typescript)
• ci: Changes to our CI configuration files and scripts (example scopes: vercel, github, cypress)
• docs: Documentation-only changes
• feat: A new feature
• fix: A bug fix
• perf: A code change that improves performance
• refactor: A code change that doesn't fix a bug, or add a feature, or improves performance
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• test: Adding missing tests or correcting existing tests

Deployment tag versioning

Has tag in common/version.go been updated or have you added bump-version label to this PR?

• No, this PR doesn't involve a new deployment, git tag, docker image tag
• Yes

Breaking change label

Does this PR have the breaking-change label?

• No, this PR is not a breaking change
• Yes

[codecov]

Codecov Report

Merging #953 (49e2804) into develop (dcd85b2) will not change coverage.
Report is 3 commits behind head on develop.
The diff coverage is n/a.

❗ Current head 49e2804 differs from pull request most recent head 0ff2e6e. Consider uploading reports for the commit 0ff2e6e to get more accurate results

@@           Coverage Diff            @@
##           develop     #953   +/-   ##
========================================
  Coverage    50.29%   50.29%           
========================================
  Files           96       96           
  Lines        10001    10001           
========================================
  Hits          5030     5030           
  Misses        4557     4557           
  Partials       414      414           

Flag	Coverage Δ
common	54.56% <ø> (ø)
coordinator	18.80% <ø> (ø)
database	42.85% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
common/types/message/message.go	51.72% <ø> (ø)