Reduce adblock filter memory usage by optimizing unused regex rules

As discovered by @atuchin-m, there is an extra ~7MB that can be saved by optimizing the regex field of NetworkFilter in adblock-rust. This was fixed in adblock-rust as of v0.5.2.

[atuchin-m]

For QA: we should verify, that browser process memory consumption became 7mb less. A possible scenario:

1. Launch browser without the fix with one saved tab about:blank
2. Wait 15 sec.
3. Check browser process memory footprint in the internal task manager (see a screenshot)
4. Repeat a few times to make the results stable (3-5 times)
5. Repeat 1-4 for browser with the fix

[kjozwiak]

Verification PASSED on Samsung S10+ running Android 12 using the following build(s):

Brave | 1.39.111 Chromium: 102.0.5005.61 (Official Build) (64-bit)
--- | ---
Revision | 0e59bcc00cc4985ce39ad31c150065f159d95ad3-refs/branch-heads/5005@{#819}
OS | Android 12; Build/SP1A.210812.016

1.38.119 (370.2 MB)	1.38.119 (318 MB)	1.38.119 (304.5 MB)	1.38.119 (302.4 MB)	1.38.119 (316.2 MB)

1.39.111 (310.6 MB)	1.39.111 (314 MB)	1.39.111 (312 MB)	1.39.111 (297.7 MB)	1.39.111 (308.3 MB)

---

Verification PASSED on Samsung Galaxy Tablet A running Android 11 using the following build(s):

Brave | 1.39.111 Chromium: 102.0.5005.61 (Official Build) (64-bit)
--- | ---
Revision | 0e59bcc00cc4985ce39ad31c150065f159d95ad3-refs/branch-heads/5005@{#819}
OS | Android 11; Build/RP1A.200720.012

1.38.119 (214.3 MB)	1.38.119 (176.2 MB)	1.38.119 (232.6 MB)	1.38.119 (204.4 MB)	1.38.119 (202.4 MB)

1.39.111 (154 MB)	1.39.111 (177.6 MB)	1.39.111 (161.4 MB)	1.39.111 (160.9 MB)	1.39.111 (149.5 MB)