Bump downstream dependencies in CI (#15096)

Co-authored-by: pyca-boringbot[bot] <pyca-boringbot[bot]+106132319@users.noreply.github.com>

Author: pyca-boringbot[bot]

.github/workflows/ci.yml

@@ -394,8 +394,8 @@ jobs:
             PATH: paramiko
           - DOWNSTREAM: pyopenssl
             REPO: pyca/pyopenssl
-            # Latest commit on the pyopenssl main branch, as of Jun 13, 2026.
-            REF: a34aa1de7e2050d3a83cef74d8265662237f8ba1
+            # Latest commit on the pyopenssl main branch, as of Jun 25, 2026.
+            REF: c6b4a5f19d681b84e9da364740ae0a416ee966f4
             PATH: pyopenssl
           - DOWNSTREAM: pyopenssl-release
             REPO: pyca/pyopenssl
@@ -414,8 +414,8 @@ jobs:
             PATH: aws-encryption-sdk-python
           - DOWNSTREAM: certbot
             REPO: certbot/certbot
-            # Latest commit on the certbot main branch, as of Jun 24, 2026.
-            REF: 90f7404b19e829a6f3d73a40ce0056164efb9329
+            # Latest commit on the certbot main branch, as of Jun 25, 2026.
+            REF: f769e35e77f1fa21a75cd5418641502dad8a37c5
             PATH: certbot
           - DOWNSTREAM: certbot-josepy
             REPO: certbot/josepy
@@ -424,8 +424,8 @@ jobs:
             PATH: josepy
           - DOWNSTREAM: mitmproxy
             REPO: mitmproxy/mitmproxy
-            # Latest commit on the mitmproxy main branch, as of Jun 18, 2026.
-            REF: c4fa9fb8c8e292512dcc708459d1555fd876fd9e
+            # Latest commit on the mitmproxy main branch, as of Jun 25, 2026.
+            REF: 3500dacba0a18f130e9d4c262393162e1538204c
             PATH: mitmproxy
           - DOWNSTREAM: scapy
             REPO: secdev/scapy
@@ -434,8 +434,8 @@ jobs:
             PATH: scapy
           - DOWNSTREAM: sigstore-python
             REPO: sigstore/sigstore-python
-            # Latest commit on the sigstore-python main branch, as of Jun 23, 2026.
-            REF: d4074942295b1cf17a383a5c430910a95fc72b24
+            # Latest commit on the sigstore-python main branch, as of Jun 25, 2026.
+            REF: 94b89686527de2e438a7c88031c39c4fc1a3cf91
             PATH: sigstore-python
     name: "Downstream tests for ${{ matrix.DOWNSTREAM }}"
     timeout-minutes: 15