Bump elliptic from 6.5.3 to 6.5.4 in /example (#266)

Bumps [elliptic](https://github.com/indutny/elliptic) from 6.5.3 to 6.5.4.
- [Release notes](https://github.com/indutny/elliptic/releases)
- [Commits](indutny/elliptic@v6.5.3...v6.5.4)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

example/yarn.lock

@@ -1285,10 +1285,10 @@ bluebird@^3.5.5:
   resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.7.2.tgz#9f229c15be272454ffa973ace0dbee79a1b0c36f"
   integrity sha512-XpNj6GDQzdfW+r2Wnn7xiSAd7TM3jzkxGXBGTtWKuSXv1xUV+azxAm8jdWZN06QTQk+2N2XB9jRDkvbmQmcRtg==
 
-bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.4.0:
-  version "4.11.9"
-  resolved "https://registry.yarnpkg.com/bn.js/-/bn.js-4.11.9.tgz#26d556829458f9d1e81fc48952493d0ba3507828"
-  integrity sha512-E6QoYqCKZfgatHTdHzs1RRKP7ip4vvm+EyRUeE2RF0NblwVvb0p6jSVeNTOFxPn26QXN2o6SMfNxKp6kU8zQaw==
+bn.js@^4.0.0, bn.js@^4.1.0, bn.js@^4.11.9:
+  version "4.12.0"
+  resolved "https://registry.yarnpkg.com/bn.js/-/bn.js-4.12.0.tgz#775b3f278efbb9718eec7361f483fb36fbbfea88"
+  integrity sha512-c98Bf3tPniI+scsdk237ku1Dc3ujXQTSgyiPUDEOe7tRkhrqridvh8klBv0HCEso1OLOYcHuCv/cS6DNxKH+ZA==
 
 bn.js@^5.0.0, bn.js@^5.1.1:
   version "5.1.3"
@@ -1342,7 +1342,7 @@ braces@~3.0.2:
   dependencies:
     fill-range "^7.0.1"
 
-brorand@^1.0.1:
+brorand@^1.0.1, brorand@^1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/brorand/-/brorand-1.1.0.tgz#12c25efe40a45e3c323eb8675a0a0ce57b22371f"
   integrity sha1-EsJe/kCkXjwyPrhnWgoM5XsiNx8=
@@ -1898,17 +1898,17 @@ electron-to-chromium@^1.3.621:
   integrity sha512-O5IVRS4sCxP2+vECAp7uHkaI8V+dKYpuCyBcLn+hqVAOy/RONd8zx+6eH7TuWSTBYs/oUrzBXkNMZuVsQd58kQ==
 
 elliptic@^6.5.3:
-  version "6.5.3"
-  resolved "https://registry.yarnpkg.com/elliptic/-/elliptic-6.5.3.tgz#cb59eb2efdaf73a0bd78ccd7015a62ad6e0f93d6"
-  integrity sha512-IMqzv5wNQf+E6aHeIqATs0tOLeOTwj1QKbRcS3jBbYkl5oLAserA8yJTT7/VyHUYG91PRmPyeQDObKLPpeS4dw==
+  version "6.5.4"
+  resolved "https://registry.yarnpkg.com/elliptic/-/elliptic-6.5.4.tgz#da37cebd31e79a1367e941b592ed1fbebd58abbb"
+  integrity sha512-iLhC6ULemrljPZb+QutR5TQGB+pdW6KGD5RSegS+8sorOZT+rdQFbsQFJgvN3eRqNALqJer4oQ16YvJHlU8hzQ==
   dependencies:
-    bn.js "^4.4.0"
-    brorand "^1.0.1"
+    bn.js "^4.11.9"
+    brorand "^1.1.0"
     hash.js "^1.0.0"
-    hmac-drbg "^1.0.0"
-    inherits "^2.0.1"
-    minimalistic-assert "^1.0.0"
-    minimalistic-crypto-utils "^1.0.0"
+    hmac-drbg "^1.0.1"
+    inherits "^2.0.4"
+    minimalistic-assert "^1.0.1"
+    minimalistic-crypto-utils "^1.0.1"
 
 emoji-regex@^7.0.1:
   version "7.0.3"
@@ -2442,7 +2442,7 @@ hash.js@^1.0.0, hash.js@^1.0.3:
     inherits "^2.0.3"
     minimalistic-assert "^1.0.1"
 
-hmac-drbg@^1.0.0:
+hmac-drbg@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/hmac-drbg/-/hmac-drbg-1.0.1.tgz#d2745701025a6c775a6c545793ed502fc0c649a1"
   integrity sha1-0nRXAQJabHdabFRXk+1QL8DGSaE=
@@ -2980,7 +2980,7 @@ minimalistic-assert@^1.0.0, minimalistic-assert@^1.0.1:
   resolved "https://registry.yarnpkg.com/minimalistic-assert/-/minimalistic-assert-1.0.1.tgz#2e194de044626d4a10e7f7fbc00ce73e83e4d5c7"
   integrity sha512-UtJcAD4yEaGtjPezWuO9wC4nwUnVH/8/Im3yEHQP4b67cXlD/Qr9hdITCU1xDbSEXg2XKNaP8jsReV7vQd00/A==
 
-minimalistic-crypto-utils@^1.0.0, minimalistic-crypto-utils@^1.0.1:
+minimalistic-crypto-utils@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/minimalistic-crypto-utils/-/minimalistic-crypto-utils-1.0.1.tgz#f6c00c1c0b082246e5c4d99dfb8c7c083b2b582a"
   integrity sha1-9sAMHAsIIkblxNmd+4x8CDsrWCo=