added SPDX header information to some files

In the end of this progress Friendica will hopefully be [REUSE](https://reuse.software) complient but this is a longterm goal.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,3 +1,9 @@
+<!--
+SPDX-FileCopyrightText: 2010 - 2024 the Friendica project
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
 ---
 name: Bug report
 about: Create a report to help us improve

.github/ISSUE_TEMPLATE/config.yml

@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2010 - 2024 the Friendica project
+#
+# SPDX-License-Identifier: CC0-1.0
+
 blank_issues_enabled: true
 contact_links:
   - name: Friendica Community Support

.github/ISSUE_TEMPLATE/feature_request.md

@@ -1,3 +1,9 @@
+<!--
+SPDX-FileCopyrightText: 2010 - 2024 the Friendica project
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
 ---
 name: Feature request
 about: Suggest an idea for this project

.github/ISSUE_TEMPLATE/question.md

@@ -1,3 +1,9 @@
+<!--
+SPDX-FileCopyrightText: 2010 - 2024 the Friendica project
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
 ---
 name: Question / Support
 about: Select this if you have a question 

.github/dependabot.yml

@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2010 - 2024 the Friendica project
+#
+# SPDX-License-Identifier: CC0-1.0
+
 # To get started with Dependabot version updates, you'll need to specify which
 # package ecosystems to update and where the package manifests are located.
 # Please see the documentation for more information: