Bump ajv from 6.10.0 to 6.12.6 in /test/end-to-end-tests (#7792)

Bumps [ajv](https://github.com/ajv-validator/ajv) from 6.10.0 to 6.12.6.
- [Release notes](https://github.com/ajv-validator/ajv/releases)
- [Commits](https://github.com/ajv-validator/ajv/compare/v6.10.0...v6.12.6)

---
updated-dependencies:
- dependency-name: ajv
  dependency-type: indirect
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Kerry Archibald <kerrya@element.io>

test/end-to-end-tests/yarn.lock

@@ -29,11 +29,11 @@ agent-base@6:
     debug "4"
 
 ajv@^6.5.5:
-  version "6.10.0"
-  resolved "https://registry.yarnpkg.com/ajv/-/ajv-6.10.0.tgz#90d0d54439da587cd7e843bfb7045f50bd22bdf1"
-  integrity sha512-nffhOpkymDECQyR0mnsUtoCE8RlX38G0rYP+wgLWFyZuUyuuojSSvi/+euOiQBIn63whYwYVIIH1TvE3tu4OEg==
+  version "6.12.6"
+  resolved "https://registry.yarnpkg.com/ajv/-/ajv-6.12.6.tgz#baf5a62e802b07d977034586f8c3baf5adf26df4"
+  integrity sha512-j3fVLgvTo527anyYyJOGTYJbG+vnnQYvE0m5mmkc1TK+nxAppkCLMIL0aZ4dblVCNoGShhm+kzE4ZUykBoMg4g==
   dependencies:
-    fast-deep-equal "^2.0.1"
+    fast-deep-equal "^3.1.1"
     fast-json-stable-stringify "^2.0.0"
     json-schema-traverse "^0.4.1"
     uri-js "^4.2.2"
@@ -282,15 +282,15 @@ extsprintf@^1.2.0:
   resolved "https://registry.yarnpkg.com/extsprintf/-/extsprintf-1.4.0.tgz#e2689f8f356fad62cca65a3a91c5df5f9551692f"
   integrity sha1-4mifjzVvrWLMplo6kcXfX5VRaS8=
 
-fast-deep-equal@^2.0.1:
-  version "2.0.1"
-  resolved "https://registry.yarnpkg.com/fast-deep-equal/-/fast-deep-equal-2.0.1.tgz#7b05218ddf9667bf7f370bf7fdb2cb15fdd0aa49"
-  integrity sha1-ewUhjd+WZ79/Nwv3/bLLFf3Qqkk=
+fast-deep-equal@^3.1.1:
+  version "3.1.3"
+  resolved "https://registry.yarnpkg.com/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz#3a7d56b559d6cbc3eb512325244e619a65c6c525"
+  integrity sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q==
 
 fast-json-stable-stringify@^2.0.0:
-  version "2.0.0"
-  resolved "https://registry.yarnpkg.com/fast-json-stable-stringify/-/fast-json-stable-stringify-2.0.0.tgz#d5142c0caee6b1189f87d3a76111064f86c8bbf2"
-  integrity sha1-1RQsDK7msRifh9OnYREGT4bIu/I=
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/fast-json-stable-stringify/-/fast-json-stable-stringify-2.1.0.tgz#874bf69c6f404c2b5d99c481341399fd55892633"
+  integrity sha512-lhd/wF+Lk98HZoTCtlVraHtfh5XYijIjalXck7saUtuanSDyLMxnHhSXEDJqHxD7msR8D0uCmqlkwjCV8xvwHw==
 
 fd-slicer@~1.1.0:
   version "1.1.0"
@@ -815,9 +815,9 @@ unbzip2-stream@1.3.3:
     through "^2.3.8"
 
 uri-js@^4.2.2:
-  version "4.2.2"
-  resolved "https://registry.yarnpkg.com/uri-js/-/uri-js-4.2.2.tgz#94c540e1ff772956e2299507c010aea6c8838eb0"
-  integrity sha512-KY9Frmirql91X2Qgjry0Wd4Y+YTdrdZheS8TFwvkbLWf/G5KNJDCh6pKL5OZctEW4+0Baa5idK2ZQuELRwPznQ==
+  version "4.4.1"
+  resolved "https://registry.yarnpkg.com/uri-js/-/uri-js-4.4.1.tgz#9b1a52595225859e55f669d928f88c6c57f2a77e"
+  integrity sha512-7rKUyy33Q1yc98pQ1DAmLtwX109F7TIfWlW1Ydo8Wl1ii1SeHieeh0HHfPeL2fMXK6z0s8ecKs9frCuLJvndBg==
   dependencies:
     punycode "^2.1.0"