[c-ares] Update to 1.17.2.

[geraldcombs]

Version 1.17.2 fixes CVE-2021-3672. Details can be found in the security
advisory at https://c-ares.haxx.se/adv_20210810.html

Describe the pull request

• What does your PR fix?

  Fixes CVE-2021-3672

• Which triplets are supported/not supported? Have you updated the CI baseline?

  !uwp, No

• Does your PR follow the maintainer guide?

  Yes

• If you have added/updated a port: Have you run ./vcpkg x-add-version --all and committed the result?

  Yes

[github-actions]

This is a new experimental fast check for PR issues. Please let us know if this bot is helpful!

After committing all other changes, the version database must be updated

git add -u && git commit
git checkout be456649fd835f6d2d676b81886fb6a58d5b52da -- versions
./vcpkg x-add-version --all

Diff

diff --git a/versions/c-/c-ares.json b/versions/c-/c-ares.json
index 4bf233e..4f9dfb1 100644
--- a/versions/c-/c-ares.json
+++ b/versions/c-/c-ares.json
@@ -1,7 +1,7 @@
 {
   "versions": [
     {
-      "git-tree": "eb20046c7f567426077db1366ef53be7918897ac",
+      "git-tree": "4a8a471e681a33c8dde0a209900ac24a2e8e7f72",
       "version": "1.17.2",
       "port-version": 0
     },

[BillyONeal]

Thanks for your contribution!