VSCode - Debug single functional test (#5599)

## What changed?
<!-- Describe what has changed in this PR -->
Added a new debug option for VSCode debugger

## Why?
<!-- Tell your future self why have you made these changes -->
This makes it easy to select and debug a single functional test.

## How did you test it?
<!-- How have you verified this change? Tested locally? Added a unit
test? Checked in staging env? -->
Manual check.

## Potential risks
<!-- Assuming the worst case, what can be broken when deploying this
change to production? -->
N/A

## Documentation
<!-- Have you made sure this change doesn't falsify anything currently
stated in `docs/`? If significant
new behavior is added, have you described that in `docs/`? -->
N/A

## Is hotfix candidate?
<!-- Is this PR a hotfix candidate or does it require a notification to
be sent to the broader community? (Yes/No) -->
No

.vscode/launch.json

@@ -1,6 +1,18 @@
 {
 	"version": "0.2.0",
 	"configurations": [
+		{
+			"name": "Debug single functional test method",
+			"type": "go",
+			"request": "launch",
+			"mode": "test",
+			"program": "${relativeFileDirname}",
+			"args": [
+				"-testify.m",
+				"${input:functionalTestSuiteMethod}"
+			]
+
+		},
 		{
 			"name": "Debug Server",
 			"type": "go",
@@ -64,5 +76,13 @@
 				"start",
 			]
 		},
+	],
+	"inputs": [
+		{
+			"type": "promptString",
+			"id": "functionalTestSuiteMethod",
+			"description": "The method name withing the functional test suite that you wish to debug.",
+			"default": "."
+		}
 	]
 }