build: niv advisory-db: update 2821ca0c -> e391658d

## Changelog for advisory-db:
Branch: master
Commits: [rustsec/advisory-db@2821ca0c...e391658d](rustsec/advisory-db@2821ca0...e391658)

* [`ae1107e4`](rustsec/advisory-db@ae1107e) Update rustsec-admin version to use new website generator ([RustSec/advisory-db⁠#810](http://r.duckduckgo.com/l/?uddg=https://github.com/RustSec/advisory-db/issues/810))
* [`a33c05d2`](rustsec/advisory-db@a33c05d) add fltk advisory
* [`5ce40487`](rustsec/advisory-db@5ce4048) Update RUSTSEC-0000-0000.md
* [`d07de997`](rustsec/advisory-db@d07de99) Update RUSTSEC-0000-0000.md
* [`35e0ea59`](rustsec/advisory-db@35e0ea5) replace with keywords
* [`a84dbc5d`](rustsec/advisory-db@a84dbc5) formatting
* [`805270dc`](rustsec/advisory-db@805270d) Assigned RUSTSEC-2021-0038 to fltk
* [`3205a091`](rustsec/advisory-db@3205a09) Report 0090-endian_trait to RustSec
* [`ef52d55d`](rustsec/advisory-db@ef52d55) Report 0109-arenavec to RustSec
* [`c2248b0e`](rustsec/advisory-db@c2248b0) arenavec: update advisory title to clarify issue
* [`f2f59e4e`](rustsec/advisory-db@f2f59e4) Assigned RUSTSEC-2021-0039 to endian_trait
* [`0bc081bb`](rustsec/advisory-db@0bc081b) Assigned RUSTSEC-2021-0040 to arenavec

Author: dfinity-bot

nix/sources.json

@@ -6,10 +6,10 @@
         "homepage": "https://rustsec.org",
         "owner": "RustSec",
         "repo": "advisory-db",
-        "rev": "2821ca0c6cacea54c5678b280b581028f942495a",
-        "sha256": "04j1dqpziqpspd53dvpqrf99j2r50ziysfrl001jvq8aj247x3sf",
+        "rev": "e391658d249ee9c578211af5f36cc8498c0391d5",
+        "sha256": "1gcarjlr35jk759ii6ynsfx0nf0rmjf074fns5mavyn2gzn4np2c",
         "type": "tarball",
-        "url": "https://github.com/RustSec/advisory-db/archive/2821ca0c6cacea54c5678b280b581028f942495a.tar.gz",
+        "url": "https://github.com/RustSec/advisory-db/archive/e391658d249ee9c578211af5f36cc8498c0391d5.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "agent-js-monorepo": {