fix: multi page mode app start event redundant logging

[zhu-xiaowei]

Description

1. fix multi page mode app start event redundant logging

General Checklist

• [x] Added new tests to cover change, if needed
• [ ] Security oriented best practices and standards are followed (e.g. using input sanitization, principle of least privilege, etc)
• [ ] Documentation update for the change if required
• [x] PR title conforms to conventional commit style
• [ ] If breaking change, documentation/changelog update with migration instructions

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (2eb9c1d) 100.00% compared to head (86bbacf) 100.00%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #31 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 24 24 Lines 987 994 +7 Branches 182 183 +1 ========================================= + Hits 987 994 +7 ``` | [Files](https://app.codecov.io/gh/awslabs/clickstream-web/pull/31?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=awslabs) | Coverage Δ | | |---|---|---| | [src/tracker/SessionTracker.ts](https://app.codecov.io/gh/awslabs/clickstream-web/pull/31?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=awslabs#diff-c3JjL3RyYWNrZXIvU2Vzc2lvblRyYWNrZXIudHM=) | `100.00% <100.00%> (ø)` | |

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.