CA2249: Consider using String.Contains instead of String.IndexOf

[himgoyalmicro]

Link to the issue description: https://learn.microsoft.com/en-us/dotnet/fundamentals/code-analysis/quality-rules/ca2249

Rule Description

When IndexOf is used to check if the result is equal to -1 or greater or equal than 0, the call can be safely substituted with Contains without an impact on performance.