tests: Use the same rustfmt configuration as the parent directory.

emilio · emilio · commit 5aec0a99a070 · 2019-10-14T14:02:12.000+02:00
This allows us to workaround/fix rust-lang/rustfmt#3799
diff --git a/tests/rustfmt.toml b/tests/rustfmt.toml
@@ -1 +1,3 @@
 normalize_doc_attributes = true
+max_width = 80
+binop_separator = "back"

Original file line number	Diff line number	Diff line change
`@@ -1 +1,3 @@`
`1`	`1`	`normalize_doc_attributes = true`
	`2`	`+max_width = 80`
	`3`	`+binop_separator = "back"`