fix: guard against undefined file path in results

[peternhale]

What does this PR do?

Guards replace in a result file for an undefined filePath

What issues does this PR fix or reference?

@W-12128219@
@W-12134988@

Issue # 1827
Issue # 1823

[WillieRuemmele]

QA Notes

---

Manifest

before

 ➜  sfdx force:source:retrieve -x manifest.xml --retrievetargetdir ./source-retrieve
Preparing retrieve request... done
(node:60004) [DEP0147] DeprecationWarning: In future versions of Node.js, fs.rmdir(path, { recursive: true }) will be removed. Use fs.rm(path, { recursive: true }) instead
(Use `node --trace-deprecation ...` to show where the warning was created)
ERROR running force:source:retrieve:  Cannot read properties of undefined (reading 'replace')

after

 ➜  sfdx force:source:retrieve -x manifest.xml --retrievetargetdir ./source-retrieve
Preparing retrieve request... done
=== Retrieved Source

 FULL NAME TYPE                     PROJECT PATH                                      
 ───────── ──────────────────────── ───────────────────────────────────────────────── 
 ldsUtils  LightningComponentBundle source-retrieve/lwc/ldsUtils/ldsUtils.js          
 ldsUtils  LightningComponentBundle source-retrieve/lwc/ldsUtils/ldsUtils.js-meta.xml 
=== Retrieved Source Warnings

 FILE NAME              PROBLEM                                                                            
 ────────────────────── ────────────────────────────────────────────────────────────────────────────────── 
 unpackaged/package.xml Entity of type 'LightningComponentBundle' named 'ldsUtilsNotFound' cannot be found 

---

CustomLabel

before:

 ➜  sfdx force:source:retrieve --retrievetargetdir=./untracked --metadata=CustomLabel:test 
Preparing retrieve request... done
ERROR running force:source:retrieve:  ENOENT: no such file or directory, stat '/Users/william.ruemmele/projects/scratches/dreamhouse-lwc/untracked/main/default'

after

 ➜  sfdx force:source:retrieve --retrievetargetdir=./untracked --metadata=CustomLabel:test 
Preparing retrieve request... done
=== Retrieved Source

 FULL NAME    TYPE         PROJECT PATH                                  
 ──────────── ──────────── ───────────────────────────────────────────── 
 CustomLabels CustomLabels untracked/labels/CustomLabels.labels-meta.xml