Change the release note slack milestone to from beta 5 to beta 4

Author: DonalMe

.github/workflows/release-notes-slack.yml

@@ -8,13 +8,13 @@ on:
   workflow_dispatch:
     inputs:
       test_milestone:
-        description: 'Test a specific milestone (beta_1, beta_5, or relnotes_deadline)'
+        description: 'Test a specific milestone (beta_1, beta_4, or relnotes_deadline)'
         required: false
         type: choice
         options:
           - ''
           - beta_1
-          - beta_5
+          - beta_4
           - relnotes_deadline
 
 jobs:

app/scripts/release_notes_slack_reminder.py

@@ -29,7 +29,7 @@
         "If any changes require a Knowledge Base article update, please let the Sumo team know via a "
         "<https://bugzilla.mozilla.org/enter_bug.cgi?product=support.mozilla.org&component=Knowledge+Base+Content|request in bugzilla>"
     ),
-    "beta_5": (
+    "beta_4": (
         "Hi! We're at the mid-point of the Fx{version} Beta cycle, which means it is time for a release notes reminder!\n\n"
         "Draft template for the Firefox {version} Release Notes are <https://whattrainisitnow.com/release-notes|here>.\n\n"
         "The DEADLINE for submissions is {relnotes_deadline}. This will give us time to make necessary edits and/or "
@@ -80,7 +80,7 @@ def determine_milestone(schedule: dict, today: date) -> tuple[str | None, dict]:
     """
     milestones = {
         "beta_1": parse_date(schedule["beta_1"]),
-        "beta_5": parse_date(schedule["beta_5"]),
+        "beta_4": parse_date(schedule["beta_4"]),
         "relnotes_deadline": parse_date(schedule["relnotes_deadline"]),
     }