Simplified installing `libssl-dev`
Proper cmake option for ssl

```
Parameterized test suite ReadonlyClientTest is defined via TEST_P, but never instantiated. None of the test cases will run. Either no INSTANTIATE_TEST_SUITE_P is provided or the only ones provided expand to nothing.

Ideally, TEST_P definitions should only ever be included as part of binaries that intend to use them. (As opposed to, for example, being placed in a library that may be linked in to get other utilities.)

To suppress this error for this test suite, insert the following line (in a non-header) in the namespace it is defined in:

GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(ReadonlyClientTest);
```