Make table subtyping invariant (#8489)

Table subtyping for imports should be invariant according to the spec: 
<img width="574" height="192" alt="image"
src="https://github.com/user-attachments/assets/dacd3d80-870a-4680-bd33-7535e70fa73f"
/>. This makes sense because the exporter might write the supertype and
the importer may later try to read a subtype which would be wrong.


The other copy of `linking.wast` is no longer relevant and doesn't pass
with these changes. Our copy:
[link](https://github.com/WebAssembly/binaryen/blob/899e44e2c3dd40795c843a91cfc326e11d64cab0/test/spec/linking.wast#L236),
upstream test:
[link](https://github.com/WebAssembly/testsuite/blob/main/linking.wast#L399-L400)
(see line 410 which differs from our copy of the test).

Part of #8261.

Author: stevenfontanella

scripts/test/shared.py

@@ -387,9 +387,6 @@ def get_tests(test_dir, extensions=[], recursive=False):
     # Requires us to write our own floating point parser
     'const.wast',
 
-    # Unlinkable module accepted
-    'linking.wast',
-
     # Invalid module accepted
     'unreached-invalid.wast',
 
@@ -423,7 +420,6 @@ def get_tests(test_dir, extensions=[], recursive=False):
     'if.wast',      # Requires more precise unreachable validation
     'imports.wast',  # Requires fixing handling of mutation to imported globals
     'proposals/threads/imports.wast',  # Missing memory type validation on instantiation
-    'linking.wast',  # Incorrectly allows covariant subtyping for table imports
     'proposals/threads/memory.wast',  # Missing memory type validation on instantiation
     'annotations.wast',  # String annotations IDs should be allowed
     'instance.wast',  # Requires support for table default elements

src/ir/runtime-table.h

@@ -47,8 +47,8 @@ class RuntimeTable {
   // be imported with the definition of `other`
   virtual bool isSubType(const Table& other) {
     return tableDefinition.addressType == other.addressType &&
-           Type::isSubType(tableDefinition.type, other.type) &&
-           size() >= other.initial && tableDefinition.max <= other.max;
+           tableDefinition.type == other.type && size() >= other.initial &&
+           tableDefinition.max <= other.max;
   }
 
   const Table* getDefinition() const { return &tableDefinition; }