Make issue_template.md point to Solana Stack Exchange before discord (#3204)

Co-authored-by: acheron <98934430+acheroncrypto@users.noreply.github.com>

.github/issue_template.md

@@ -1 +1,4 @@
-⚠️ Don't use issues for support questions ("How does x feature work in Anchor? How to do x in Anchor?"). Use the discord instead https://discord.gg/NHHGSXAnXk (but don't ping maintainers). ⚠️
+⚠️ Don't use issues for support questions ("How does x feature work in Anchor? How to do x in Anchor?"). Instead: 
+
+ - Check [Solana Stack Exchange](https://solana.stackexchange.com/) - chances are someone has already had the same issue, and there's already an answer there. If not, write a new question! 
+ - See [the Anchor Discord](https://discord.gg/NHHGSXAnXk) (but don't ping maintainers). ⚠