Revert "Add spdx dependency"

This reverts commit 3358af5.

Gemfile

@@ -53,9 +53,6 @@ gem 'descriptive-statistics'
 # for sorting hashes by keys
 gem 'deep_sort'
 
-# used for validating project spdx licenses
-gem "spdx", "~> 4.1"
-
 # DO NOT change rails version without also changing composite_primary_keys version
 # https://github.com/composite-primary-keys/composite_primary_keys
 RAILS_VERSION = '~> 7.0.1'

Gemfile.lock

@@ -457,7 +457,6 @@ GEM
     patience_diff (1.2.0)
       optimist (~> 3.0)
     pg (1.4.3)
-    polyglot (0.3.5)
     process-metrics (0.2.1)
       console (~> 1.8)
       samovar (~> 2.1)
@@ -679,8 +678,6 @@ GEM
     solargraph-rails (0.3.1)
       activesupport
       solargraph (>= 0.41.1)
-    spdx (4.1.3)
-      treetop (~> 1.6)
     sprockets (4.1.1)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
@@ -712,8 +709,6 @@ GEM
     tins (1.31.1)
       sync
     traces (0.6.1)
-    treetop (1.6.12)
-      polyglot (~> 0.3)
     typeprof (0.21.3)
       rbs (>= 1.8.1)
     tzinfo (2.0.6)
@@ -845,7 +840,6 @@ DEPENDENCIES
   simplecov
   solargraph (>= 0.45.0)
   solargraph-rails (>= 0.3.1)
-  spdx (~> 4.1)
   sqlite3
   super_diff
   test-prof