Add GIT_SSL_NO_VERIFY for self-signed cert on Gitea

Runner CI jobs fail with gnutls_handshake() error because
catthehacker/ubuntu container doesn't trust Gitea's private certificate.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitea/workflows/ci.yaml

@@ -6,6 +6,9 @@ on:
   pull_request:
     branches: [main]
 
+env:
+  GIT_SSL_NO_VERIFY: "true"
+
 jobs:
   lint-and-test:
     runs-on: ubuntu-22.04

.gitea/workflows/dvc-data-update.yaml

@@ -7,6 +7,9 @@ on:
       - "dvc.yaml"
       - "dvc.lock"
 
+env:
+  GIT_SSL_NO_VERIFY: "true"
+
 jobs:
   validate-data:
     runs-on: ubuntu-latest

.gitea/workflows/train.yaml

@@ -8,6 +8,9 @@ on:
       - "configs/**"
       - "dvc.yaml"
 
+env:
+  GIT_SSL_NO_VERIFY: "true"
+
 jobs:
   train:
     runs-on: ubuntu-latest