zscaler_zpa: fix IPProtocol mapping

[efd6]

Proposed commit message

zscaler_zpa: fix IPProtocol mapping

The ingest pipeline was previously incorrectly mapping the values of
IPProtocol to network.type when it should be mapped to network.transport.

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.
• I have verified that any added dashboard complies with Kibana's Dashboard good practices

Author's Checklist

• [ ]

How to test this PR locally

Related issues

• Fixes [zscaler_zpa]: ingest pipeline incorrectly maps IP Protocol to network type #13980

Screenshots

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🚀 Benchmarks report

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Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube

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💚 Build Succeeded

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• Commit: 1ab74b7

cc @efd6

[elasticmachine]

Pinging @elastic/security-service-integrations (Team:Security-Service Integrations)

[elastic-vault-github-plugin-prod]

Package zscaler_zpa - 1.22.3 containing this change is available at https://epr.elastic.co/package/zscaler_zpa/1.22.3/