gopls: Update test cases.

Update test files for different types of reference relationships between asm and Go.

Updates golang/go#71754

Author: groot-guo

gopls/internal/test/marker/testdata/references/asm.txt

@@ -1,5 +1,4 @@
-
-
+Test of asm references.
 
 -- example/label_example.s --
 TEXT ·JumpDemo(SB), $0-0
@@ -21,4 +20,3 @@ GLOBL ·myGlobal(SB), NOPTR, 8
 TEXT ·UseGlobal(SB), $0-0
     MOVQ ·myGlobal(SB), AX //@loc(refMyGlobal, "·myGlobal")
     RET
-

gopls/internal/test/marker/testdata/references/asm_go.txt

@@ -1,15 +1,5 @@
 This test validates the References request functionality in Go assembly files.
 
-It ensures that references to both exported (`Add`) and unexported (`sub`) functions are correctly identified across Go and assembly files. The test covers:
-- Locating the definition of functions in both Go and assembly files.
-- Identifying all references to the functions (`Add` and `sub`) within the Go and assembly files.
-
-The test includes:
-- `Add`: An exported function with references in both Go and assembly files.
-- `sub`: An unexported function with references in both Go and assembly files, including a usage in Go code (`var _ = sub`).
-
-The assembly file demonstrates portable assembly syntax and verifies cross-file reference handling.
-
 -- go.mod --
 module example.com
 go 1.24