Update the minimum Firefox verson to 68 (#19191)

This is still a version from 3 years ago, so it is a very small change, but it
does bring us to a version that has wasm-bigint enabled, which will
help #19156

ChangeLog.md

@@ -27,6 +27,7 @@ See docs/process.md for more on how version tagging works.
   since we no longer need scan linker inputs using `llvm-nm`.  It also
   completely removes the need for the `REVERSE_DEPS` settings which has now
   been deprecated. (#18905)
+- Bump the default minimum Firefox version from 65 to 68 (#19191).
 
 3.1.36 - 04/16/23
 -----------------

src/settings.js

@@ -1745,10 +1745,10 @@ var AUTO_NATIVE_LIBRARIES = true;
 // versions >= MIN_FIREFOX_VERSION
 // are desired to work. Pass -sMIN_FIREFOX_VERSION=majorVersion to drop support
 // for Firefox versions older than < majorVersion.
-// Firefox ESR 60.5 (Firefox 65) was released on 2019-01-29.
+// Firefox ESR 68 was released on July 9, 2019.
 // MAX_INT (0x7FFFFFFF, or -1) specifies that target is not supported.
 // [link]
-var MIN_FIREFOX_VERSION = 65;
+var MIN_FIREFOX_VERSION = 68;
 
 // Specifies the oldest version of desktop Safari to target. Version is encoded
 // in MMmmVV, e.g. 70101 denotes Safari 7.1.1.