[7.17](backport #3399) Remove known non-working agent versions (#3421)

* Remove known non-working agent versions (#3399)

* Skip known non-working agent versions for agent upgrade tests

There is a know issue fixed in agent where agents fail to upgrade
because they download the wrong package (fixed in 8.6.0). This commit
removes such versions from the test since they won't be released anymore
(hence no point in backporting the fix).

(cherry picked from commit d07fc67)

# Conflicts:
#	e2e/_suites/fleet/features/upgrade_agent.feature

* Fix merge conflicts

---------

Co-authored-by: Paolo Chilà <[email protected]>

e2e/_suites/fleet/features/upgrade_agent.feature

@@ -2,16 +2,24 @@
 Feature: Upgrade Agent
   Scenarios for upgrading the Agent from past releases.
 
-Scenario Outline: Upgrading an installed agent from <stale-version>
-  Given a "<stale-version>" stale agent is deployed to Fleet with "tar" installer
+  Scenario Outline: Upgrading an installed agent from <stale-version>
+    Given a "<stale-version>" stale agent is deployed to Fleet with "tar" installer
     And the agent is listed in Fleet as "online"
     And certs are installed
     And the "elastic-agent" process is "restarted" on the host
-  When agent is upgraded to "latest" version
-  Then agent is in "latest" version
-Examples: Stale versions
-| stale-version |
-| latest |
-| 7.16.0 |
-| 7.15.0 |
-| 7.14.0 |
+    When agent is upgraded to "latest" version
+    Then agent is in "latest" version
+    Examples: Stale versions
+      | stale-version    |
+      | latest           |
+      | 7.17.10-SNAPSHOT |
+
+# These are the version of elastic agent that still have the bug solved in
+# https://github.com/elastic/elastic-agent/pull/1791
+    @skip
+    Examples: Skipped stale versions
+      | stale-version |
+      | 7.17.8        |
+      | 7.16.0        |
+      | 7.15.0        |
+      | 7.14.0        |