Changes

TiCDC: Increase memory limits for TiCDC integration test pods to improve stability (#4090)

## Increase Memory Limits for TiCDC Integration Test Pipelines

This PR updates the memory resource limits for several TiCDC integration
test pipelines to improve stability and prevent out-of-memory (OOM)
failures during test execution.

### Why this change?
Recent test runs have shown intermittent failures due to memory
exhaustion, particularly in heavier integration scenarios. Increasing
the memory allocation ensures tests have sufficient resources to
complete reliably, reducing flakiness and improving overall CI/CD
pipeline stability.

### Changes Made:
- **Kafka Integration Light Tests**: Memory increased from 8Gi to 16Gi
for both `pull_cdc_kafka_integration_light` and
`pull_cdc_kafka_integration_light_next_gen`.
- **MySQL Integration Heavy Tests**: Memory increased from 16Gi to 32Gi
for both `pull_cdc_mysql_integration_heavy` and
`pull_cdc_mysql_integration_heavy_next_gen`.
- **Storage Integration Light Tests**: Memory increased from 8Gi to 16Gi
for both `pull_cdc_storage_integration_light` and
`pull_cdc_storage_integration_light_next_gen`.

### Impact:
- CPU limits remain unchanged across all pipelines.
- These adjustments align with observed resource usage patterns and are
expected to eliminate OOM-related test failures without
over-provisioning.

---------

Signed-off-by: tenfyzhong <tenfy@tenfy.cn>
Co-authored-by: wuhuizuo <wuhuizuo@126.com>
 (commit: e1f9d7b)