Revert "Update jeromq to 0.6.0 (#1314)"

Seems some of its classes are a problem for the next commit's changes,
giving errors like:
```
Error:  error while loading SocketType,
Error:  class file org/zeromq/SocketType.class is broken, reading aborted with class java.lang.RuntimeException
Error:  bad constant pool index: 0 at pos: 1840
Error:  -- [E006] Not Found Error: /home/runner/work/almond/almond/modules/shared/channels/src/main/scala/almond/channels/zeromq/ZeromqSocketImpl.scala:20:14
Error:  20 |  socketType: SocketType,
Error:     |              ^^^^^^^^^^
Error:     |              Not found: type SocketType
Error:     |
Error:     | longer explanation available when compiling with `-explain`
```

This reverts commit e6dc050.

project/deps.sc

@@ -56,7 +56,7 @@ object Deps {
   def fs2(sv: String) =
     if (sv.startsWith("2.")) ivy"co.fs2::fs2-core:3.9.4" else ivy"co.fs2:fs2-core_2.13:3.9.4"
   def jansi  = ivy"org.fusesource.jansi:jansi:2.4.1"
-  def jeromq = ivy"org.zeromq:jeromq:0.6.0"
+  def jeromq = ivy"org.zeromq:jeromq:0.5.4"
   def jsoniterScalaCore =
     ivy"com.github.plokhotnyuk.jsoniter-scala::jsoniter-scala-core:${Versions.jsoniterScala}"
   def jsoniterScalaMacros =