vector: stop overriding default features

So far, features were overridden to remove unix from the default feature set.
However, e.g. oniguruma is in the dependency tree and only works on isUnix platforms, so the feature was always on anyways.

This additionally deals with the problem that adding the rdkafka?/… resulted in an empty feature list.
Alternatively, this could have been worked around by adding rdkafka/… to the feature list since rdkafka is enabled by another feature in the list,
but this is no longer necessary.

pkgs/tools/misc/vector/default.nix

@@ -20,28 +20,6 @@
   cmake,
   perl,
   git,
-  # nix has a problem with the `?` in the feature list
-  # enabling kafka will produce a vector with no features at all
-  enableKafka ? false,
-  # TODO investigate adding various "vendor-*"
-  # "disk-buffer" is using leveldb TODO: investigate how useful
-  # it would be, perhaps only for massive scale?
-  features ? (
-    [
-      "api"
-      "api-client"
-      "enrichment-tables"
-      "sinks"
-      "sources"
-      "sources-dnstap"
-      "transforms"
-      "component-validation-runner"
-    ]
-    # the second feature flag is passed to the rdkafka dependency
-    # building on linux fails without this feature flag (both x86_64 and AArch64)
-    ++ lib.optionals enableKafka [ "rdkafka?/gssapi-vendored" ]
-    ++ lib.optional stdenv.hostPlatform.isUnix "unix"
-  ),
   nixosTests,
   nix-update-script,
 }:
@@ -119,9 +97,6 @@ rustPlatform.buildRustPackage {
   CARGO_PROFILE_RELEASE_LTO = "fat";
   CARGO_PROFILE_RELEASE_CODEGEN_UNITS = "1";
 
-  buildNoDefaultFeatures = true;
-  buildFeatures = features;
-
   # TODO investigate compilation failure for tests
   # there are about 100 tests failing (out of 1100) for version 0.22.0
   doCheck = false;
@@ -158,7 +133,6 @@ rustPlatform.buildRustPackage {
   '';
 
   passthru = {
-    inherit features;
     tests = {
       inherit (nixosTests) vector;
     };