remove compilation database (#95)

The compilation_database step was causing a "conflicting artifacts" condition
when running Bazel tests in CLion. When this is removed, tests run cleanly.

The original `grailbio/bazel-compilation-database` project is in maintenance
mode. If something like this is needed again in the future, we can add it back.

BUILD.bazel

@@ -1,5 +1,3 @@
-load("@com_grail_bazel_compdb//:aspects.bzl", "compilation_database")
-
 cc_library(
     name = "spectator",
     srcs = [
@@ -51,12 +49,3 @@ cc_test(
         "@com_google_googletest//:gtest",
     ],
 )
-
-compilation_database(
-    name = "spectator_compdb",
-    testonly = True,
-    targets = [
-        ":spectator",
-        ":spectator_test",
-    ],
-)