doc: Update container package overview

[JonasBakys0]

Description:

• Updates incorrect overview for container package
• issue

Checklist:

• I have formatted my code using goimport and golangci-lint.
• All new code is covered by unit tests.
• This PR does not decrease the overall code coverage.
• I have reviewed the code comments and documentation for clarity.

[JonasBakys0]

I dropped the link idea because it seemed too complicated. For example:

• If I want to use the doc link I face this issue:
  
• And with Links, it's hard to maintain them. What if cassandra package location change

// [Cassandra]: https://pkg.go.dev/gofr.dev/pkg/gofr/datasource/cassandra

Either way, please correct me if I'm wrong. Go is new to me and don't know how idiomatic documentation should look like in go 😄

[Umang01-hash]

@JonasBakys0 the tests and the pipeline is failing due to these errors:

Please fix them.