Fix resuming job when job has optional data parameters

This fixes
```
ERROR    galaxy.tools.actions:__init__.py:683 Cannot remap rerun dependencies.
Traceback (most recent call last):
  File "/Users/mvandenb/src/galaxy/lib/galaxy/tools/actions/__init__.py", line 664, in _remap_job_on_rerun
    self.__remap_parameters(job_to_remap, jtid, jtod, out_data)
  File "/Users/mvandenb/src/galaxy/lib/galaxy/tools/actions/__init__.py", line 694, in __remap_parameters
    input_values = {p.name: json.loads(p.value) for p in job_to_remap.parameters}
  File "/Users/mvandenb/src/galaxy/lib/galaxy/tools/actions/__init__.py", line 694, in <dictcomp>
    input_values = {p.name: json.loads(p.value) for p in job_to_remap.parameters}
  File "/usr/local/Cellar/python@3.9/3.9.10/Frameworks/Python.framework/Versions/3.9/lib/python3.9/json/__init__.py", line 339, in loads
    raise TypeError(f'the JSON object must be str, bytes or bytearray, '
TypeError: the JSON object must be str, bytes or bytearray, not
NoneType
```

Optional data inputs or optional selects are stored as `None` (super
inconsistent, since most other parameters are stored as JOSN. We should
create "basic_2.py" using pydantic at one point not too far into the
future ...). This means we can't call `json.loads` on these. Fortunately
this is the only place we do it, and we don't need to consider optional
parameters here anyway.

lib/galaxy/tools/actions/__init__.py

@@ -675,12 +675,13 @@ class DefaultToolAction:
         return remapped_hdas
 
     def __remap_parameters(self, job_to_remap, jtid, jtod, out_data):
-        input_values = {p.name: json.loads(p.value) for p in job_to_remap.parameters}
+        input_values = {p.name: json.loads(p.value) for p in job_to_remap.parameters if p.value is not None}
         old_dataset_id = jtod.dataset_id
         new_dataset_id = out_data[jtod.name].id
         input_values = update_dataset_ids(input_values, {old_dataset_id: new_dataset_id}, src='hda')
         for p in job_to_remap.parameters:
-            p.value = json.dumps(input_values[p.name])
+            if p.name in input_values:
+                p.value = json.dumps(input_values[p.name])
         jtid.dataset = out_data[jtod.name]
         jtid.dataset.hid = jtod.dataset.hid
         log.info(f'Job {job_to_remap.id} input HDA {jtod.dataset.id} remapped to new HDA {jtid.dataset.id}')

lib/galaxy_test/api/test_workflows.py

@@ -967,6 +967,7 @@ steps:
           cond_param_inner: true
           input1:
             $link: 0/out_file1
+    thedata: null
   cat:
     tool_id: cat1
     in:

test/functional/tools/identifier_multiple_in_conditional.xml

@@ -16,6 +16,7 @@
                 </conditional>
             </when>
         </conditional>
+        <param name="thedata" type="data" optional="true" label="Optional dummy data"/>
     </inputs>
     <outputs>
         <data name="output1" format="tabular" from_work_dir="output1" />