Restructure test files (#10415)

tests/format/graphql/string/string.graphql

@@ -0,0 +1,52 @@
+query X($a: Int) @relay(meta: "{\"lowPri\": true}") { a }
+
+"""abc"""
+type T {
+  a: Int
+}
+
+"""
+abc
+"""
+type T {
+  a: Int
+}
+
+"""
+  a
+    b
+      c
+         """
+type T { a: Int }
+
+type Foo {
+"""
+This is a description
+of the `one` field.
+"""
+  one: Type
+}
+
+type Foo {
+q("docs" field: String): Type
+q("A long string of description of the field parameter to make this break" field: String): Type
+q("""docs""" field: String): Type
+}
+
+enum Enum {
+"""
+Description of `one`
+"""
+one
+}
+
+input Input {
+"""
+Description of `one`
+"""
+one: string
+}
+
+{
+  foo(input: {multiline: "ab\ncd"}) { id }
+}