[Release] logzio-logs-collector align to new global structure

[8naama]

Description

• Change secret values to global to prevent duplicate values in the parent chart
  • secrets.secretParam >> global.secretParam
  • Update secrets.customEndpoint >> global.customLogsEndpoint to avoid conflicts with other charts
• K8s secret resource configuration has been renamed secrets >> secret
• Upgrade otel/opentelemetry-collector-contrib image to v.0.109.0
  • Note: we can't upgrade beyond v.0.109.0, since starting at v.0.110.0+, the time field (which holds the original log timestamp) has been removed. This change was made because it was duplicate - appearing both as Timestamp at the log root and as Attributes.time. To upgrade to a newer version without losing this field, we would need to update our OTEL exporter to explicitly include the log's Timestamp as an additional field.
• Move changelog from README.md >> CHANGELOG.md
• Update readme
• Align the command in E2E test

What type of PR is this?

(check all applicable)

• 🍕 Feature
• 🐛 Bug Fix
• 🧑‍💻 Code Refactor
• 🔥 Performance Improvements
• ✅ Test
• 🤖 Build / CI
• ⏩ Revert

Added tests?

• 👍 yes
• 🙅 no, because they aren't needed
• 🙋 no, because I need help from somebody