Use OpenPGP instead of GPG when referring to the spec or its artifacts

While GPG is still one of the most prevalent implementations, it is just
one among many. We are dealing here with OpenPGP artifacts, so spell
that out explicitly. This is more relevant now that GnuPG has opted out
of the IETF OpenPGP working group, and will not be implementing future
revisions of the specification.

Author: guillemj

.github/ISSUE_TEMPLATE/join.yml

@@ -28,7 +28,7 @@ body:
     id: signed-message
     attributes:
       label: Your signed membership application
-      description: Please prove your association with Debian with a gpg-signed membership request.
+      description: Please prove your association with Debian with an OpenPGP signed membership request.
       placeholder: |
         -----BEGIN PGP SIGNED MESSAGE-----
         Hash: SHA512

.github/workflows/join.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check signature of join request
-        id: gpg-check
+        id: openpgp-check
         env:
           DATA: ${{ github.event.issue.body }}
         run: |
@@ -26,10 +26,10 @@ jobs:
           gpg --homedir mygpg --verify --status-fd 1 file.txt 2>/dev/null  || true
           # 0: success
           # 2: no public key
-          echo "extracting GPG key ID..."
+          echo "extracting OpenPGP certificate ID..."
           key=$(gpg --homedir mygpg --verify --status-fd 1 file.txt 2>/dev/null  | awk '{if ($2 == "ERRSIG") print $9; else if ($2 == "VALIDSIG") print $3}')
           echo "KEY: ${key}"
-          echo "fetching GPG key from keyring.debian.org..."
+          echo "fetching OpenPGP certificate from keyring.debian.org..."
           gpg --homedir mygpg --keyserver keyring.debian.org --recv-keys "$key"
           debuser=$(gpg --homedir mygpg -k ${key} | grep -E "^uid[[:space:]].*@debian.org>" | sed -e 's|.*<\([^@]*\)@debian.org>.*|\1|' | head -1)
           userid=$(gpg --homedir mygpg -k ${key} | grep -E "^uid[[:space:]].*\[" | sed -e 's|.*][[:space:]]*||' -e '/^[[:space:]]*$/d' | head -1)
@@ -40,8 +40,8 @@ jobs:
           echo "DEBUSER=${debuser}" >> $GITHUB_OUTPUT
           echo "USERID=${userid}" >> $GITHUB_OUTPUT
     outputs:
-      deb-username: ${{ steps.gpg-check.outputs.DEBUSER }}
-      pgp-userid: ${{ steps.gpg-check.outputs.USERID }}
+      deb-username: ${{ steps.openpgp-check.outputs.DEBUSER }}
+      pgp-userid: ${{ steps.openpgp-check.outputs.USERID }}
 
   decline:
     name: Decline membership