ci(gevent): pin greenlet for legacy gevent versions

tox.ini

@@ -36,10 +36,11 @@ envlist =
     dogpile_contrib-py{311}-dogpilecache{08,09,10,11,}
     futures_contrib-py27-futures{30,31,32,}
     futures_contrib-py{35,36,37,38,39,310,311}
-    gevent_contrib-py27-gevent{11,12,13}-sslmodules
-    gevent_contrib-py{35,36}-gevent{11,12,13}-sslmodules3-sslmodules
-    gevent_contrib-py{37,38}-gevent{13,14}-sslmodules3-sslmodules
-    gevent_contrib-py{39}-gevent{209,2012,211}-sslmodules3-sslmodules
+    gevent_contrib-py27-gevent{11,12,13}-greenlet1-sslmodules
+    gevent_contrib-py{35,36}-gevent{11,12,13}-greenlet1-sslmodules3-sslmodules
+    gevent_contrib-py{37,38}-gevent{13,14}-greenlet1-sslmodules3-sslmodules
+    gevent_contrib-py{39}-gevent209-greenlet1-sslmodules3-sslmodules
+    gevent_contrib-py{39}-gevent{2012,211}-sslmodules3-sslmodules
     gevent_contrib-py{310}-gevent{218}-sslmodules3-sslmodules
     gevent_contrib-py{311}-gevent{228}-sslmodules3-sslmodules
     kombu_contrib-py{27,35,36}-kombu{40,41,42,43,44,45,46,}
@@ -69,16 +70,17 @@ envlist =
     py{27,35,36,37,38,39,310,311}-opentracer
     py{35,36,37,38,39,310,311}-opentracer_asyncio
     py{35,36,37,38,39,310,311}-opentracer_tornado-tornado{44,45,50,60,}
-    py{27,35,36}-opentracer_gevent-gevent{11,12}
-    py{37,38}-opentracer_gevent-gevent{13,14}
-    py{39}-opentracer_gevent-gevent{209,2012,211}
+    py{27,35,36}-opentracer_gevent-gevent{11,12}-greenlet1
+    py{37,38}-opentracer_gevent-gevent{13,14}-greenlet1
+    py{39}-opentracer_gevent-gevent209-greenlet1
+    py{39}-opentracer_gevent-gevent{2012,211}-greenlet1
     py{310,311}-opentracer_gevent-gevent{228}
 
 isolated_build = true
 
 requires = virtualenv<=20.2.1
 
-[testenv:gevent_contrib-py{37,38}-gevent{13,14}-sslmodules3-sslmodules]
+[testenv:gevent_contrib-py{37,38}-gevent{13,14}-greenlet1-sslmodules3-sslmodules]
 # Wheels for gevent segfault pretty easily
 install_command=python -m pip install --no-binary=gevent {opts} {packages}
 usedevelop = true
@@ -177,6 +179,7 @@ deps =
     gevent211: gevent>=21.1,<21.2
     gevent218: gevent>=21.8,<21.9
     gevent228: gevent>=22.8,<22.10
+    greenlet1: greenlet>=1,<2
     # kombu using deprecated shims removed in importlib-metadata 5.0
     kombu{40,41,42,43,44,45,46,}: importlib_metadata<5.0; python_version<'3.8'
     kombu: kombu