Allow error block to access {{taskrun.value}} of failed ForEach

[paulgrainger85]

Feature description

Take the example flow here. If this flow breaks during an iteration of ForEach, we should be able to access the value at the current {{taskrun.value}} . However currently this is not passed through as we are no longer in the flowable context

id: errors
namespace: demo

variables:
  current_iteration: ""

tasks:
- id: iterateObjects
  type: io.kestra.plugin.core.flow.ForEach
  concurrencyLimit: 1
  values: '["/tmp/kestra-wd/data/good.csv", "/tmp/kestra-wd/data/error.csv"]'
  tasks:
    - id: debugCurrentIteration
      type: io.kestra.plugin.core.debug.Return
      format: "{{ taskrun.value }}"

    - id: printFileName
      type: io.kestra.plugin.core.log.Log
      message: Let's read CSV {{ taskrun.value }}

    - id: downloadFile
      type: io.kestra.plugin.core.http.Download
      uri: '{{ taskrun.value }}'
  errors:
    - id: printErrorMsg
      type: io.kestra.plugin.core.log.Log
      message: Error reading {{ taskrun.value }}

[anna-geller]

error.value will be extra information printed for Flowable that do some sort of iteration

• taskrun.items for ForEachItem
• taskrun.value for ForEach
• loop.iterationCount for WaitFor
• case for Switch task