Build: Update browsers tested in BrowserStack

Changes:
1. Remove Safari 17
2. Add iOS 26
3. Add Firefox 128 (due to there being Firefox 128 ESR in the past)

Closes gh-602
Ref gh-601

Author: mgol

.github/workflows/browserstack.yml

@@ -29,12 +29,9 @@ jobs:
           - 'IE_9'
           - 'Safari_latest'
             # JTR doesn't take into account the jump from Safari 18 to 26,
-            # so we need to specify versions explicitly. Also, while BrowserStack
-            # already added macOS Tahoe with Safari 26, it's not a stable release
-            # yet, so we need to test on Safari 17 as well.
+            # so we need to specify versions explicitly.
             # See https://github.com/jquery/jquery-test-runner/issues/17
           - 'Safari_18'
-          - 'Safari_17'
           - 'Chrome_latest'
           - 'Chrome_latest-1'
           - 'Opera_latest'
@@ -43,12 +40,14 @@ jobs:
           - 'Edge_18'
           - 'Firefox_latest'
           - 'Firefox_latest-1'
+          - 'Firefox_128'
           - 'Firefox_115'
           - 'Firefox_102'
           - 'Firefox_91'
           - 'Firefox_78'
           - 'Firefox_60'
           - 'Firefox_48'
+          - '__iOS_26'
           - '__iOS_18'
           - '__iOS_17'
           - '__iOS_16'