[prim_{alert_receiver|dom_2_share}] Assertion memory footprint warnings

Noticed these when running chip simulations:
```

Warning-[SVA-OPTCOV-LMFA] Large memory footprint assertion
../src/lowrisc_prim_alert_0/rtl/prim_alert_receiver.sv, 335
The assertion 'InBandInitSequence_A' has the potential to consume a large
amount of memory.
Please examine the assertion for the use of large or unbounded delays and
repetitions.

Warning-[SVA-OPTCOV-LMFA] Large memory footprint assertion
../src/lowrisc_prim_prim_dom_and_2share_0.1/rtl/prim_dom_and_2share.sv, 106
The assertion 'UnmaskedAndMatched_A' has the potential to consume a large
amount of memory.
Please examine the assertion for the use of large or unbounded delays and
repetitions.
```

Start with the assertions named InBandInitSequence_A in src/lowrisc_prim_alert_0/rtl/prim_alert_receiver.sv:335 and UnmaskedAndMatched_A in src/lowrisc_prim_prim_dom_and_2share_0.1/rtl/prim_dom_and_2share.sv:106. Reproduce the chip-simulation warnings, inspect the cited assertions and their delays or repetitions, and verify that the large-memory-footprint warnings are addressed.

Written by the indexing model from the issue text.