Update the --merge-extern-blocks tests

Author: pvdrz

bindgen-tests/tests/expectations/tests/merge_extern_blocks_post_1_82.rs

@@ -0,0 +1,14 @@
+// bindgen-flags: --merge-extern-blocks --enable-cxx-namespaces --rust-target=1.82 -- --target=x86_64-unknown-linux
+int foo();
+typedef struct Point {
+    int x;
+} Point;
+int bar();
+
+namespace ns {
+    int foo();
+    typedef struct Point {
+        int x;
+    } Point;
+    int bar();
+}

bindgen-tests/tests/expectations/tests/merge_extern_blocks_pre_1_82.rs

@@ -0,0 +1,14 @@
+// bindgen-flags: --merge-extern-blocks --enable-cxx-namespaces --rust-target=1.81 -- --target=x86_64-unknown-linux
+int foo();
+typedef struct Point {
+    int x;
+} Point;
+int bar();
+
+namespace ns {
+    int foo();
+    typedef struct Point {
+        int x;
+    } Point;
+    int bar();
+}