lib: TLS session ticket caching reworked

Described in detail in internal doc TLS-SESSIONS.md

Main points:
- use a new `ssl_peer_key` for cache lookups by connection filters
- recognize differences between TLSv1.3 and other tickets
  * TLSv1.3 tickets are single-use, cache can hold several of them for a peer
  * TLSv1.2 are reused, keep only a single one per peer
- differentiate between ticket BLOB to store (that could be persisted) and object instances
- use put/take/return pattern for cache access
- remember TLS version, ALPN protocol, time received and lifetime of ticket
- auto-expire tickets after their lifetime

Closes #15774

tests/http/test_02_download.py

@@ -617,7 +617,7 @@ class TestDownload:
         earlydata = {}
         reused_session = False
         for line in r.trace_lines:
-            m = re.match(r'^\[t-(\d+)] EarlyData: (\d+)', line)
+            m = re.match(r'^\[t-(\d+)] EarlyData: (-?\d+)', line)
             if m:
                 earlydata[int(m.group(1))] = int(m.group(2))
                 continue

tests/http/test_14_auth.py

@@ -134,4 +134,4 @@ class TestAuth:
         # Depending on protocol, we might have an error sending or
         # the server might shutdown the connection and we see the error
         # on receiving
-        assert r.exit_code in [55, 56], f'{self.dump_logs()}'
+        assert r.exit_code in [55, 56], f'{r.dump_logs()}'