Limit nightly CI runs to original repository (#4148)

Author: holgerd77

.github/workflows/node-versions.yml

@@ -6,6 +6,7 @@ on:
 
 jobs:
   tests:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     strategy:
       matrix:

.github/workflows/other-nightly.yml

@@ -9,6 +9,7 @@ env:
 
 jobs:
   test-ethash:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -25,6 +26,7 @@ jobs:
         working-directory: ${{ github.workspace }}/packages/ethash
 
   test-client:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -41,6 +43,7 @@ jobs:
         working-directory: ${{ github.workspace }}/packages/client
 
   test-devp2p:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -57,6 +60,7 @@ jobs:
         working-directory: ${{ github.workspace }}/packages/devp2p
 
   test-wallet:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5

.github/workflows/vm-nightly-test.yml

@@ -13,6 +13,7 @@ defaults:
 
 jobs:
   test-vm-api:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -29,6 +30,7 @@ jobs:
   #     - run: npm run test:API:browser
 
   test-vm-state:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -46,6 +48,7 @@ jobs:
       - run: npm run test:state:allForks
 
   test-vm-blockchain:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -64,6 +67,7 @@ jobs:
         working-directory: '${{ env.cwd }}'
 
   test-vm-slow:
+    if: github.repository == 'ethereumjs/ethereumjs-monorepo'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5