tests: fix clippy::doc_lazy_continuation findings

Fixes clippy findings of the form:

```
error: doc list item missing indentation
  --> rustls-platform-verifier/src/tests/verification_real_world/mod.rs:17:5
   |
17 | //! with the measures mentioned in the next paragraphs, the operating system
   |     ^
   |
   = help: if this is supposed to be its own paragraph, add a blank line
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#doc_lazy_continuation
   = note: `-D clippy::doc-lazy-continuation` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::doc_lazy_continuation)]`
```

rustls-platform-verifier/src/tests/verification_real_world/mod.rs

@@ -14,13 +14,13 @@
 //! effort  
 //!
 //! * If these certificates are ever revoked then it is possible that, even if
-//! with the measures mentioned in the next paragraphs, the operating system
-//! might learn of the revocation externally and cause the tests to fail.
+//!   with the measures mentioned in the next paragraphs, the operating system
+//!   might learn of the revocation externally and cause the tests to fail.
 //!
 //! * Some operating systems, Windows in particular, download the set of
-//! trusted roots dynamically as-needed. If there is a failure during that
-//! fetching then the trust anchors for these certificates might not be
-//! trusted by the operating system's root store.
+//!   trusted roots dynamically as-needed. If there is a failure during that
+//!   fetching then the trust anchors for these certificates might not be
+//!   trusted by the operating system's root store.
 //!
 //! XXX: These tests should be using a stapled OCSP responses so that the
 //! (operating-system-based) verifier doesn't try to fetch an OCSP