Possible Inaccurate Detection of Existing Runtime Configuration in config.toml

https://github.com/spinkube/runtime-class-manager/blob/c65f3562aabfca4681c034f09afd4d5a513ee732/internal/containerd/configure.go#L61

The current implementation checks for the existence of a specific runtimeName in the config.toml file uses a simple substring search. This approach, while straightforward, has several limitations and potential pitfalls:

1. Partial Matches: The method can yield false positives if runtimeName is a substring of another unrelated configuration or value within the file.
2. Context Ignorance: The detection does not consider the context or the exact location of runtimeName within the file, leading to inaccurate assessments if the name appears in comments or as part of other keys/values.
3. Case Sensitivity: The search is case-sensitive, missing occurrences with different capitalizations.
4. Inefficiency with Large Files: Loading and searching through the entire file content as a string might not be efficient for large configuration files.

Proposed Solution: Use a proper TOML parser to accurately and efficiently verify the existence of runtimeName within the correct context.

Impact: Addressing this issue will enhance reliability and efficiency, reducing the risk of incorrect configurations.