fix: 🐛 transformArrayToMap fieldsArray may undefined

[lhoopox]

Parsing can be problematic when the contract result contains an array of enumerated types

[vizipi]

Pull request analysis by VIZIPI

Below you will find who is the most qualified team member to review your code.
This analysis includes his/her work on the code included in this Pull request, in addition to their experience in code affected by these changes ( partly found within the list of potential missing files below )   Feedback always welcome

Reviewers with knowledge related to these changes

Match %	Person	Commit Count	Common Files
100.00 %	AbigailDeng	23	7
57.14 %	potter-sun	5	4

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Potential missing files from this Pull request

files commonly committed with a subset of this pr, but not committed this time. (click to collapse)

File	Percentile	rate
test/unit/chain/chainMethod.test.js	50.00 %	1 out of 2 times
package.json	50.00 %	1 out of 2 times
src/util/utils.js	50.00 %	1 out of 2 times
test/unit/chain/index.test.js	50.00 %	1 out of 2 times
test/unit/util/merkleTree.test.js	50.00 %	1 out of 2 times
test/unit/util/bloom.test.js	50.00 %	1 out of 2 times
test/unit/contract/contractMethod.test.js	50.00 %	1 out of 2 times
types/contract/contractMethod.d.ts	50.00 %	1 out of 2 times
test/unit/contract/index.test.js	50.00 %	1 out of 2 times
README.md	50.00 %	1 out of 2 times

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Committed file ranks

(click to expand)

97.64%[dist/aelf.umd.js]

66.93%[src/util/transform.js]

92.52%[test/unit/util/transform.test.js]

97.64%[dist/aelf.cjs.js]

80.71%[test/unit/util/token.proto.json]

96.46%[dist/aelf.cjs.js.map]

96.46%[dist/aelf.umd.js.map]