std, compiler-rt: remove test names where applicable

Tests with no names are executed when using `zig test` regardless of the
`--test-filter` used. Non-named tests should be used when simply
importing unit tests from another file. This allows `zig test` to find
all the appropriate tests, even when using `--test-filter`.

lib/std/json.zig

@@ -2657,7 +2657,7 @@ test "json.parser.dynamic" {
     try testing.expect(mem.eql(u8, large_int.NumberString, "18446744073709551615"));
 }
 
-test "import more json tests" {
+test {
     _ = @import("json/test.zig");
     _ = @import("json/write_stream.zig");
 }