Added new API to get list of github issues (#3170)

Co-authored-by: Praveen Kuttappan <praveen.kuttappan@gmail.com>

eng/common/scripts/Invoke-GitHubAPI.ps1

@@ -187,6 +187,33 @@ function New-GitHubIssue {
     -MaximumRetryCount 3
 }
 
+function Get-GitHubIssues {
+  param (
+    [Parameter(Mandatory = $true)]
+    $RepoOwner,
+    [Parameter(Mandatory = $true)]
+    $RepoName,
+    $CreatedBy,
+    [Parameter(Mandatory = $true)]
+    $Labels,
+    [ValidateNotNullOrEmpty()]
+    [Parameter(Mandatory = $true)]
+    $AuthToken
+  )
+
+  $uri = "$GithubAPIBaseURI/$RepoOwner/$RepoName/issues?labels=$Labels"
+
+  if ($CreatedBy) {
+    $uri += "&creator=$CreatedBy"
+  }
+
+  return Invoke-RestMethod `
+    -Method GET `
+    -Uri $uri `
+    -Headers (Get-GitHubApiHeaders -token $AuthToken) `
+    -MaximumRetryCount 3
+}
+
 function Add-GitHubIssueComment {
   param (
     [Parameter(Mandatory = $true)]