Support read-only Numba types

[brandonwillard]

This PR adds support for read-only types via our loosely established Variable.tag.indestructible flag.

This PR also closes #1221 by simply ignoring those errors and disabling warn_unused_ignores for that specific module.

[codecov]

Codecov Report

Merging #1343 (53b6c18) into main (5dee3c7) will increase coverage by 0.00%.
The diff coverage is 94.73%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1343   +/-   ##
=======================================
  Coverage   74.27%   74.27%           
=======================================
  Files         175      175           
  Lines       48886    48887    +1     
  Branches    10375    10375           
=======================================
+ Hits        36311    36312    +1     
  Misses      10282    10282           
  Partials     2293     2293           

Impacted Files	Coverage Δ
aesara/link/numba/dispatch/basic.py	92.25% <90.00%> (+0.01%)	⬆️
aesara/link/numba/dispatch/extra_ops.py	98.00% <100.00%> (ø)
aesara/link/numba/dispatch/nlinalg.py	100.00% <100.00%> (ø)
aesara/link/numba/dispatch/sparse.py	92.53% <100.00%> (ø)
aesara/scan/op.py	85.13% <100.00%> (ø)