Delete unused //build_tests:karma

We haven't been using karma and I don't have the enthusiasm to port it
to rules_js. Instead, let's just delete it.

Signed-off-by: Philipp Schrader <philipp.schrader@gmail.com>
Change-Id: I7f67fba2b6e4b2e3cbeba2a7fc546c416b1145e4
diff --git a/build_tests/BUILD b/build_tests/BUILD
index 1e9043b..bfdd76e 100644
--- a/build_tests/BUILD
+++ b/build_tests/BUILD
@@ -4,7 +4,6 @@
 load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
 load("//tools/build_rules:apache.bzl", "apache_wrapper")
 load("@rules_rust//rust:defs.bzl", "rust_binary", "rust_library", "rust_test")
-load("@npm//@bazel/concatjs:index.bzl", "karma_web_test_suite")
 load("//tools/build_rules:autocxx.bzl", "autocxx_library")
 
 cc_test(
@@ -166,23 +165,6 @@
     srcs = ["basic.ts"],
 )
 
-ts_project(
-    name = "ts_test",
-    testonly = True,
-    srcs = ["basic_test.ts"],
-    deps = [
-        ":build_tests_ts",
-        "@npm//@types/jasmine",
-    ],
-)
-
-karma_web_test_suite(
-    name = "karma",
-    testonly = True,
-    target_compatible_with = ["@platforms//os:linux"],
-    deps = [":ts_test"],
-)
-
 rust_library(
     name = "rust_in_cc_rs",
     srcs = ["rust_in_cc.rs"],