Filter out inaccessible tasks from release (#3133)

Task/Issue URL:
https://app.asana.com/0/1204006570077678/1208036161861761/f
Tech Design URL:
CC:

**Description**:
When a task is deleted or private, we will remove it from the release,
given that it will make it fail.

**Steps to test this PR**:
I tested this by using an internal release and adding an `exit 0` on
line `279` (to ensure the script doesn’t move forward). I added a delete
task to the release and tested the id that wasn’t part of the `task_ids`
array.

**Definition of Done**:

* [x] Does this PR satisfy our [Definition of
Done](https://app.asana.com/0/1202500774821704/1207634633537039/f)?

---
###### Internal references:
[Pull Request Review
Checklist](https://app.asana.com/0/1202500774821704/1203764234894239/f)
[Software Engineering
Expectations](https://app.asana.com/0/59792373528535/199064865822552)
[Technical Design
Template](https://app.asana.com/0/59792373528535/184709971311943)
[Pull Request
Documentation](https://app.asana.com/0/1202500774821704/1204012835277482/f)

scripts/update_asana_for_release.sh

@@ -54,7 +54,17 @@ fetch_current_release_notes() {
 get_task_id() {
 	local url="$1"
 	if [[ "$url" =~ ${task_url_regex} ]]; then
-		echo "${BASH_REMATCH[1]}"
+		local task_id="${BASH_REMATCH[1]}"
+		local http_code
+		http_code="$(curl -fLSs "${asana_api_url}/tasks/${task_id}?opt_fields=gid" \
+			-H "Authorization: Bearer ${ASANA_ACCESS_TOKEN}" \
+			--write-out '%{http_code}' \
+			--output /dev/null)"
+		if [[ "$http_code" -eq 200 ]]; then
+			echo "${task_id}"
+		else
+			echo ""
+		fi
 	fi
 }
 
@@ -265,7 +275,11 @@ handle_internal_release() {
 
 	local task_ids=()
 	while read -r line; do
-		task_ids+=("$(get_task_id "$line")")
+		local task_id
+		task_id="$(get_task_id "$line")"
+		if [[ -n "$task_id" ]]; then
+			task_ids+=("$task_id")
+		fi
 	done <<< "$(find_task_urls_in_git_log "$last_release_tag")"
 
 	# 2. Fetch current release notes from Asana release task.
@@ -327,7 +341,11 @@ get_tasks_in_last_internal_release() {
 	# 2. Convert Asana task URLs from git commit messages to task IDs
 	local task_ids=()
 	while read -r line; do
-		task_ids+=("$(get_task_id "$line")")
+		local task_id
+		task_id="$(get_task_id "$line")"
+		if [[ -n "$task_id" ]]; then
+			task_ids+=("$task_id")
+		fi
 	done <<< "$(find_task_urls_in_git_log "$last_release_tag")"
 
 	# 3. Construct a HTML list of task IDs