New Rule T0037: Use .Test suffix namespace

[pavel-mikula-sonarsource]

When there's a Test namespace based on project name with .Test in it, and follow up namespace Something, and there's a using importing the Something directly, raise an issue to use .Test suffix instead.

using SonarAnalyzer.Xxx.Something;

namespace SonarAnalyzser.Xxx.Test.Something // Noncompliant

namespace SonarAnalyzser.Xxx.Something.Test// Compliant, the using can be removed (we don't care in this rule)

We don't want to raise everywhere to reduce noise. For example :

namespace SonarAnalyzer.Enterprise.SymbolicExecution.Test.TestFramework; // This still makes sense as is
namespace SonarAnalyzer.Test.Rules; // This is acceptable