Rust: Fix bad join

```
Evaluated relational algebra for predicate DataFlowImpl::RustDataFlow::pathResolveToVariantCanonicalPath/2#dc73aca0@34414869 with tuple counts:
          422639   ~3%    {3} r1 = JOIN `DataFlowImpl::resolveExtendedCanonicalPath/3#0454a346` WITH Synth::Synth::TPathAstNode#a7913307 ON FIRST 1 OUTPUT Lhs.1, Lhs.0, Lhs.2
        73033499   ~7%    {6}    | JOIN WITH DataFlowImpl::MkVariantCanonicalPath#ab1ecb00 ON FIRST 1 OUTPUT Lhs.1, Lhs.2, Rhs.3, _, Rhs.1, Rhs.2
                          {4}    | REWRITE WITH Tmp.3 := "::", Out.3 := (In.4 ++ Tmp.3 ++ In.5), TEST Out.3 = InOut.1 KEEPING 4
          170993   ~1%    {2}    | SCAN OUTPUT In.0, In.2
                          return r1
```

Author: hvitved

rust/ql/lib/codeql/rust/dataflow/internal/DataFlowImpl.qll

@@ -957,8 +957,8 @@ module RustDataFlow implements InputSig<Location> {
   /** Holds if path `p` resolves to variant `v`. */
   private predicate pathResolveToVariantCanonicalPath(PathAstNode p, VariantCanonicalPath v) {
     exists(CrateOriginOption crate, string path, string name |
-      resolveExtendedCanonicalPath(p, crate, path + "::" + name) and
-      v = MkVariantCanonicalPath(crate, path, name)
+      resolveExtendedCanonicalPath(p, pragma[only_bind_into](crate), path + "::" + name) and
+      v = MkVariantCanonicalPath(pragma[only_bind_into](crate), path, name)
     )
   }