[ImgBot] Optimize images

*Total -- 1,548.55kb -> 743.34kb (52%)

/assets/images/spectra-th/Bi-207.png -- 94.27kb -> 31.06kb (67.06%)
/assets/images/spectra-th/Am-241.png -- 29.35kb -> 12.30kb (58.09%)
/assets/images/spectra-th/Cs-137.png -- 111.43kb -> 46.86kb (57.95%)
/assets/images/spectra-th/Pb-210.png -- 30.58kb -> 13.42kb (56.11%)
/assets/images/spectra-th/Cr-51.png -- 30.86kb -> 13.79kb (55.3%)
/assets/images/spectra-th/Eu-152.png -- 38.59kb -> 17.39kb (54.95%)
/assets/images/spectra-th/Re-188.png -- 29.65kb -> 13.39kb (54.85%)
/assets/images/spectra-th/Re-186.png -- 30.29kb -> 13.85kb (54.26%)
/assets/images/spectra-th/I-131.png -- 34.22kb -> 15.78kb (53.87%)
/assets/images/spectra-th/Fe-55.png -- 139.46kb -> 64.36kb (53.85%)
/assets/images/spectra-th/I-125.png -- 31.72kb -> 14.64kb (53.83%)
/assets/images/spectra-th/Er-169.png -- 35.38kb -> 16.37kb (53.72%)
/assets/images/spectra-th/Co-57.png -- 26.55kb -> 12.29kb (53.7%)
/assets/images/spectra-th/Tc-99m.png -- 26.88kb -> 12.51kb (53.44%)
/assets/images/spectra-th/Ba-133.png -- 31.73kb -> 15.12kb (52.35%)
/assets/images/spectra-th/Hg-197m.png -- 36.17kb -> 17.41kb (51.86%)
/assets/images/spectra-th/Ba-131.png -- 38.10kb -> 18.50kb (51.43%)
/assets/images/spectra-th/Ac-225.png -- 36.92kb -> 18.00kb (51.24%)
/assets/images/spectra-th/Ra-226.png -- 41.71kb -> 20.36kb (51.19%)
/assets/images/spectra-th/CeramicPipe.png -- 33.45kb -> 16.37kb (51.08%)
/assets/images/spectra-th/Sm-153.png -- 35.59kb -> 17.91kb (49.67%)
/assets/images/spectra-th/ThoriumSource.png -- 52.19kb -> 26.42kb (49.38%)
/assets/images/spectra-th/Zeunerite.png -- 50.62kb -> 26.10kb (48.44%)
/assets/images/spectra-th/Na-22.png -- 35.87kb -> 18.63kb (48.07%)
/assets/images/spectra-th/Lu-176.png -- 40.24kb -> 20.92kb (48%)
/assets/images/spectra-th/La-138.png -- 37.51kb -> 19.53kb (47.94%)
/assets/images/spectra-th/Lu-177.png -- 44.07kb -> 23.00kb (47.81%)
/assets/images/spectra-th/K-40.png -- 41.05kb -> 21.50kb (47.62%)
/assets/images/spectra-th/RadiumDial.png -- 46.96kb -> 24.69kb (47.43%)
/assets/images/spectra-th/Co-60.png -- 38.33kb -> 20.28kb (47.09%)
/assets/images/spectra-th/Pitchblende.png -- 41.12kb -> 22.23kb (45.94%)
/assets/images/spectra-th/Ge-68_Ga-68.png -- 39.36kb -> 21.34kb (45.79%)
/assets/images/spectra-th/Uranium-glaze.png -- 47.00kb -> 25.66kb (45.41%)
/assets/images/spectra-th/I-124.png -- 42.79kb -> 23.47kb (45.15%)
/assets/images/spectra-th/Fiestaware.png -- 48.57kb -> 27.87kb (42.62%)

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