zeta: Improve efficiency and clarity of license detection patterns (#37242)

See discussion on #36564

Adds a simple ad-hoc substring matching pattern language which allows
skipping a bounded number of chars between matched substrings. Before
this change compiling the regex was taking ~120ms on a fast machine and
~8mb of memory. This new version is way faster and uses minimal memory.

Checked the behavior of this vs by running it against 10k licenses that
happened to be in my home dir. There were only 4 differences of behavior
with the regex implementation, and these were false negatives for the
regex implementation that are true positives with the new one.

Of the ~10k licenses in my home dir, ~1k do not match one of these
licenses, usually because it's GPL/MPL/etc.

Release Notes:

- N/A

crates/zeta/license_patterns/apache-2.0-reference-pattern

@@ -0,0 +1,14 @@
+-- 0..512
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http
+-- 0..1
+://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.