WIP [dbnode] Prevent bootstrap of shared rev. index

[linasm]

What this PR does / why we need it:

Fixes #

Special notes for your reviewer:
Based on #2803 (read only namespaces)

Does this PR introduce a user-facing and/or backwards incompatible change?:

Does this PR require updating code package or user-facing documentation?:

[codecov]

Codecov Report

Merging #2810 (9fb631e) into master (7e31044) will increase coverage by 0.8%.
The diff coverage is 92.3%.

@@            Coverage Diff            @@
##           master    #2810     +/-   ##
=========================================
+ Coverage    71.3%    72.2%   +0.8%     
=========================================
  Files        1079     1115     +36     
  Lines       98596   100525   +1929     
=========================================
+ Hits        70389    72611   +2222     
+ Misses      23253    22977    -276     
+ Partials     4954     4937     -17     

Flag	Coverage Δ
aggregator	76.0% <ø> (-0.1%)	⬇️
cluster	85.0% <ø> (-0.1%)	⬇️
collector	84.3% <ø> (ø)
dbnode	79.5% <92.3%> (+3.8%)	⬆️
m3em	74.4% <ø> (ø)
m3ninx	73.0% <ø> (-0.2%)	⬇️
m3nsch	51.1% <ø> (?)
metrics	17.2% <ø> (-2.7%)	⬇️
msg	74.2% <ø> (ø)
query	69.2% <ø> (+0.3%)	⬆️
x	80.5% <ø> (+0.5%)	⬆️

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