Move inactive Pipelines reviewers to alumni

The contributor ladder states that contributors may be moved to
emeritus status [due to extended periods of inactivity](https://github.com/tektoncd/community/blob/main/process/contributor-ladder.md#inactivity).
This commit moves Pipelines reviewers with < 5 reviews ever and 0 reviews
in 2022 (based on https://gist.github.com/afrittoli/8aa0e878a87652f785bb9e5ec4c98400)
to alumni status.
This will help prevent Pipelines pull-requests from being auto-assigned
to inactive contributors.

To those who have been moved to alumni status, thank you for your
contributions to this project, and you are welcome to return
to active reviewer status at any time.

org/org.yaml

@@ -417,38 +417,27 @@ orgs:
         maintainers:
         - bobcatfish
         members:
-        - savitaashture
-        - barthy1
-        - FogDong
         - waveywaves
         - sthaha
         - abayer
         - shashwathi
         - skaegi
         - nader-ziada
-        - AlanGreene
         - wlynch
         - dlorenc
         - dibbles
         - pritidesai
         - jerop
-        - GregDritschler
         - danielhelfand
         - jlpettersson
         - dibyom
-        - Peaorl
         - piyush-garg
         - chmouel
         - psschwei
         - hrishin
         - ImJasonH
-        - EliZucker
         - vdemeester
         - mattmoor
-        - dwnusbaum
-        - othomann
-        - houshengbo
-        - vincent-pli
         - withlin
         - afrittoli
         - pierretasci
@@ -458,7 +447,18 @@ orgs:
         - chuangw6
         - XinruZhang
         # alumni:
+        # AlanGreene
+        # barthy1
+        # dwnusbaum
+        # EliZucker
+        # FogDong
+        # GregDritschler
+        # houshengbo
+        # othomann
+        # Peaorl
+        # savitaashture
         # sbwsg
+        # vincent-pli
         privacy: closed
         repos:
           pipeline: read