Rust: Accept result regression.

Presumably because of a change in context, e.g. the module wrapping
this test now, or the different inputs.  Either way we *should* be
able to get the result, and what we *actually* get in our analysis
doesn't change here either.  We've just slightly changed the test
and exposed a gap.

Author: geoffw0

rust/ql/test/library-tests/dataflow/sources/net/InlineFlow.expected

@@ -530,8 +530,6 @@ nodes
 | test.rs:501:19:501:24 | buffer | semmle.label | buffer |
 subpaths
 testFailures
-| test.rs:400:44:400:64 | //... | Missing result: hasTaintFlow=url |
-| test.rs:405:44:405:64 | //... | Missing result: hasTaintFlow=url |
 #select
 | test.rs:12:10:12:23 | remote_string1 | test.rs:11:26:11:47 | ...::get | test.rs:12:10:12:23 | remote_string1 | $@ | test.rs:11:26:11:47 | ...::get | ...::get |
 | test.rs:15:10:15:23 | remote_string2 | test.rs:14:26:14:47 | ...::get | test.rs:15:10:15:23 | remote_string2 | $@ | test.rs:14:26:14:47 | ...::get | ...::get |

rust/ql/test/library-tests/dataflow/sources/net/test.rs

@@ -397,12 +397,12 @@ mod futures_rustls {
             // using the `AsyncReadExt::read` extension method (higher-level)
             let mut buffer1 = [0u8; 64];
             let bytes_read1 = futures::io::AsyncReadExt::read(&mut reader, &mut buffer1).await?; // we cannot resolve the `read` call, which comes from `impl<R: AsyncRead + ?Sized> AsyncReadExt for R {}` in `async_read_ext.rs`
-            sink(&buffer1[..bytes_read1]); // $ hasTaintFlow=url
+            sink(&buffer1[..bytes_read1]); // $ MISSING: hasTaintFlow=url
 
             let mut buffer2 = [0u8; 64];
             let bytes_read2 = reader.read(&mut buffer2).await?; // we cannot resolve the `read` call, which comes from `impl<R: AsyncRead + ?Sized> AsyncReadExt for R {}` in `async_read_ext.rs`
 
-            sink(&buffer2[..bytes_read2]); // $ hasTaintFlow=url
+            sink(&buffer2[..bytes_read2]); // $ MISSING: hasTaintFlow=url
         }
 
         let mut reader2 = futures::io::BufReader::new(reader);