[MIPS] Fix symbols being filtered out from target side of diff if target object contains .NON_MATCHING markers (#250)

* Fix filtering out symbols from the target side that have a symbol with the same name and a `.NON_MATCHING` suffix.

- Target side: Show all the symbols except the `.NON_MATCHING` ones.
- Base side: Ignore all the `.NON_MATCHING` symbols and also ignore the ones with the same name without the suffix

* fmt

* comment

* tests

* fmt tests

* maybe this could fix wasm?

* Fix wasm?

* fmt

* Move `DiffSide` to `diff` mod

* Update the stuff the advisories CI told me to

objdiff-core/tests/snapshots/arch_mips__read_mips.snap

@@ -1,5 +1,6 @@
 ---
 source: objdiff-core/tests/arch_mips.rs
+assertion_line: 10
 expression: obj
 ---
 Object {
@@ -51,6 +52,7 @@ Object {
             {},
         ],
         ignored_symbols: {},
+        diff_side: Base,
     },
     endianness: Little,
     symbols: [