Workflows: Improve cpu time limits (#18352)

* improve the explanation about cpu time limits and its relationship withg the duration of a Workflow

Author: bruxodasilva

src/content/docs/workflows/reference/limits.mdx

@@ -16,8 +16,8 @@ Many limits are inherited from those applied to Workers scripts and as documente
 | ----------------------------------------- | ----------------------- | --------------------- |
 | Workflow class definitions per script     | 1MB max script size per [Worker size limits](/workers/platform/limits/#account-plan-limits) | 10MB max script size per [Worker size limits](/workers/platform/limits/#account-plan-limits)
 | Total scripts per account                 | 100 | 500 (shared with [Worker script limits](/workers/platform/limits/#account-plan-limits) |
-| Compute time per Workflow                 | 10 seconds | 30 seconds of [active CPU time](/workers/platform/limits/#cpu-time) |
-| Duration (wall clock) per `step`          | Unlimited | Unlimited - e.g. waiting on network I/O calls or querying a database |
+| Compute time per step [^3]                | 10 seconds | 30 seconds of [active CPU time](/workers/platform/limits/#cpu-time) |
+| Duration (wall clock) per step [^3]       | Unlimited | Unlimited - for example, waiting on network I/O calls or querying a database |
 | Maximum persisted state per step          | 1MiB (2^20 bytes) | 1MiB (2^20 bytes) |
 | Maximum state that can be persisted per Workflow instance | 100MB | 1GB |
 | Maximum `step.sleep` duration             | 365 days (1 year) [^1] |
@@ -31,4 +31,6 @@ Many limits are inherited from those applied to Workers scripts and as documente
 
 [^2]: Workflow state and logs will be retained for 3 days on the Workers Free plan and for 7 days on the Workers Paid plan.
 
+[^3]: A Workflow instance can run forever, as long as each step does not take more than the CPU time limit and the maximum number of steps per Workflow is not reached.
+
 <Render file="limits_increase" product="workers" />