Fix o.e.osgi.tests warnings in I-build

The following warnings are fixed:
```
1. WARNING in
/src/org/eclipse/osgi/tests/container/TestModuleContainer.java
 (at line 733)
Module c1 = installDummyModule("c1_v1.MF", "c1_v1", container);
The value of the local variable c1 is not used
2. WARNING in
/src/org/eclipse/osgi/tests/container/TestModuleContainer.java
 (at line 734)
Module c2 = installDummyModule("c2_v1.MF", "c2_v1", container);
The value of the local variable c2 is not used
3. WARNING in
/src/org/eclipse/osgi/tests/container/TestModuleContainer.java
 (at line 735)
Module c3 = installDummyModule("c3_v1.MF", "c3_v1", container);
The value of the local variable c3 is not used
4. WARNING in
/src/org/eclipse/osgi/tests/container/TestModuleContainer.java
 (at line 737)
Module c5 = installDummyModule("c5_v1.MF", "c5_v1", container);
The value of the local variable c5 is not used
```

Also the class had a mixture of static import for asserts and not which
is fixed to use only static imports now.