rego-v1: Future-proofing ir, loader, profiler, and refactor pkg tests to be 1.0 compatible (#7021)

Updating tests in packages:

* ir
* loader
* profiler
* refactor

Signed-off-by: Johan Fylling <johan.dev@fylling.se>

loader/internal/embedtest/bar/bar.rego

@@ -1,3 +1,4 @@
 package bar
+import rego.v1
 
-p = true { true }
+p = true if { true }

loader/loader_test.go

@@ -52,8 +52,9 @@ func TestLoadRego(t *testing.T) {
 
 	files := map[string]string{
 		"/foo.rego": `package ex
+import rego.v1
 
-p = true { true }`}
+p = true if { true }`}
 
 	test.WithTempFS(files, func(rootDir string) {
 		moduleFile := filepath.Join(rootDir, "foo.rego")